Adult help required with cutting tool.
Do seeds germinate better in paper or on soil? Which one provides a better start and which one ends up with larger and hardier plants? Find out by doing our simple seed germination science experiment. Bear in mind that if you want to showcase these seeds and plants in a science project you’ll need to plant them well in advance of a science fair, if that’s what your project is for.
There are several ways to germinate seeds. If you germinate the seed in the dirt and pot, there is no need for transplanting. If you germinate in a paper then you do have to transplant but it may be faster to germinate.
What’s the best way to germinate?
You Will Need
3 dixie cups
6 paper towels
paper dessert plates
1/2 gallon distilled water
Small notebook and pencil
Small paring knife (you will need an adult’s help with this part)
What to Do
1. Add about two inches of potting soil to three cups
2. Slice a small slice in the six seeds with the knife (ask an adult to help you with this) and plant three of them about ¼ inch deep in the cups with the soil.
3. Take the other three seeds and wet the paper towels and place a seed inside them and then place each one on a plate.
4. Water the soil, but don’t over water
5. Place all the seeds in a room that is dark and quite warm and water as they begin to dry out. Make sure not to overwater and keep all the seeds in the same conditions. Keep them all in the same darkness and give them equal amounts of water so that your experiment offers good results.
Monitor the state of the seeds daily. Note when they begin to germinate, which ones germinated first and which have the thicker and better stalk on the plants.. Note their growth rate in a week and in two weeks.
Chart or graph the outcome and arrive at a conclusion that you can share with the other students.
Ready for some additional information and experiments on Seed germination or gardening? Find out about the benefical insects that can live in your garden?
The DIY Electric Train is amazing fun, easy to build, and a wealth of science that can be discussed at many levels. It does take a bit of concentration and a few key tips to make it work, which is why we put this at the 4th grade level.
But you be the guide. The more you want to help in its construction, the younger the student can be.
… and the deeper you want the student to get into the “why it works” part, the older they can be.
This featured video was created by “The Bearded Science Guy” and he does a nice job of introducing the topic at the middle school level.
So How Does The DIY Electric Train Work?
As was seen at about the 0:45 mark in the video, the “train” components from left to right were positioned so that we had a S pole then N pole for the 1st magnet, a S pole then North for the battery itself, but the last magnet was opposite at N then S pole.DIY Electric Train Battery Setup
When the “train” is placed into the coil, because the magnets are actually touching the copper wire, electricity from the battery flows through the magnets into the coil. When electrons flow through a coiled wire, that induces a magnetic field. And that magnetic field has polarity as well.
Because of the way the batteries are positioned, one end of the train is attracted (or pulled) by the coil’s induced magnetic field and the other end is repelled (pushed) by it.
But that only works if you put the right end of the train in the coil. If your first attempt does not work, just turn the train around and try again!
Other Things To Do
Coil separation, or the spacing between the coils matters and I recommend you test that to see how. If you make them too wide, then the coil’s magnetic field isn’t as strong and the train moves slower. Too tight such that the coils touch and the same thing happens. But something in between (like in the above video) works really well. Test this!
The type of magnets on the end can change things dramatically. Not all magnets are equal and “normal” magnets like you might use on your refrigerator won’t work. You need the new rare earth super magnets (neodymium magnets as noted in the video) for the project to work. The “old” magnets just don’t have enough strength.
The super magnets come in various “n-number” strengths up to n52, but n48’s work pretty good if you are using AAA batteries (and they are cheaper).
The number of magnets are also important. The more you put on (one would think), the more magnetic strength you have and the faster the train will go. Or will it?
Yes it will, up to a point. Once the magnets get too heavy then friction starts to slow things down.
If you want another source that discusses in detail how each variable affects the outcome, you can look here.
But I think it is more fun to try it and see for yourself … then try to figure out why.
Need More Detail For Older Students?
The above is a good start, but we really didn’t talk about how a magnetic field is induced in a wire, and we didn’t discuss how you can predict which direction that field will go in and just how that interacts with the “train” to be sure it will move through the coil.
We didn’t define how much current will be provided by the battery and we did not calculate field strengths.
We didn’t use right hand rules … in other words, there is a LOT that can be done to turn this simple, fun and entertaining experiment into a head scratch-er for high school science students!
After riding the rails with this one, take a look here for a simple but fun project: http://how-things-work-science-projects.com/lemon-battery-project/
A Fourth Grade Science Project: Compass Deflection
Does a compass always have to point North? If not, why not?
What if we propose that it points in the direction of the stronger magnetic field? How could we prove that?
Earth’s magnetic field is certainly there, but as we saw in the magnetic science projects page, electricity and magnetism are definitely related. So, if we have a stronger magnetic field than that of the Earth’s, might we be able to deflect what a compass needle will show as North?
And what about the magnetic field induced from current flowing through a wire. Is any of that related?
Hmmm … let’s see …
This fourth grade science project is designed to introduce young students to the concept of magnetism by using everyday items they are most likely already familiar with. In this project, we will show that a compass does not always have to point North. Instead, it will point in the direction of a stronger magnetic field. And, as we will soon see, the flow of current through a wire will deflect the compass needle, which means something magnetic must be going on there as well …
Recommend groups of 3 to 5.
You will need the following for each lab station:
The photo on the right shows the fourth grade science project kit for several experiments, but you will only need the following from that:
- About a 1 Ft section of the insulated wire
- 1 D cell battery
- 1 Compass
- 1 Magnet (any size will do)
For this project … just remove about 1” of insulation from each end of the insulated wire sections.
That’s it. Now it’s time to have fun …
Before anybody gets the material out, we need to discuss a couple fourth grade science project safety items. First, we will be working with batteries. Yes, they are the same ones they use at home in flashlights, games, radios, etc. The difference here is that they will not be in a protective cover. Also, we will be hooking them up with wires. That does several things:
– The batteries will run down quickly if the wires are left on too long
– The batteries will get hot if left connected too long
– The wire will get hot if connected too long
– Rare, but a battery could rupture if connected too long
No panics here … just please insist they wear the safety glasses.
Then tell’em all to have fun with the experiment, but if the wire starts to get hot, disconnect it from the battery and wait a minute or two before continuing.
Now let’s get started …
Have the students take the battery, the 1 Ft section of insulated wire and the compass out. Show them where North is, and mention that the compass should point there now. You might need to explain that a compass is really just a magnet, so it will also point toward metal, like screws and braces under the desk top. Have them move the compass around until it points as close to North as possible. This just gives them a reference point to start with.
Mention again about the wire getting hot if connected to the battery too long, then demonstrate how to hold the wire ends on the battery to complete an electric circuit. You can use a rubber band to keep the wire connected if desired.
Tell them that the current flows from the positive terminal (the one with a + sign by it) to the negative terminal. As the current flows in the wire, a magnetic field is created around it. We can see that in our fourth grade science project by watching the compass needle as we move it close to the wire.
Have one student in each group connect the wire ends to the battery, while another moves the compass around. If you have a fairly advanced class, tell to put their thumb in the direction of the current (thumb pointing away from the positive terminal). If their fingers are straight out when doing that, they will be pointing in the direction the North end of the compass will point.
Then explain that the magnetic field really goes all the way around the wire, and if they curl their fingers while keeping the thumb pointed in the direction of the current, they can see what that means as well. (If they are having trouble grasping the concept today … just leave this part out till next year!)
Have them move the compass around the wire to show that the magnetic field really does “push” the compass needle straight away from the wire all the way around. At some point, have them disconnect the battery to see what happens. They should see the needle point back toward North.
The photo below shows what they should see.
Repeat the process with only the compass and the magnet. They should see that the needle of the compass will move with the magnet as well.
So What Just Happened?
For the teacher – A magnetic field can be created by current (electrons moving through our wire), or by a magnet itself.
In either case, the compass needle will follow the stronger magnetic field, be that the magnet, the magnetic field induced by current through the wire, or the earth itself. If only the earth’s magnetic field is involved, the the compass points to (magnetic) north. But, if we have a stronger magnetic field close to the compass, that may not be the case!
For the students – we can make a compass tell us “North” isn’t really North by simply putting a magnet, or a magnetic field close to it. So, we need to make sure we know what is the “driving force” on the compass before we rely on it to give us directions!
… and for a more “out of the box” type projects for Magnetic Science Experiments, the following should help …
Many of the items that you need for this experiment will be lower in cost and may even be in your home already. If you’re looking for something to do that younger kids will enjoy and that won’t take long to accomplish, this is the experiment you want.
YOU WILL NEED:
Magnetite (if available)
Several general-purpose bar magnets of different strengths
One very strong Bar or U magnet
One small hammer
This second grade science project requires one small step in advance. One or two days before the class project, put at least one paperclip for each project group you will have on the north side of the very strong magnet and leave them there.
Ask the students if any have used a magnet before. Let them give as many examples as they can, then ask if any of them ever made a magnet. If yes, great! Ask if they remember how. Chances are that nobody will raise their hand, so ask how many would like to learn how to make a magnet to get the fun started. If you have enough students for a couple groups, give each group a set of bar magnets and about a dozen paper clips. Please be sure to set some second grade science project lab rules … like the paperclips stay on the table until it is time to do the experiment, and then, only one person touches them at a time, etc.
Explain that magnets have a north and south pole, just like the earth. If this lab followed a compass project similar to this one, great … break out a compass from last time to remind them that it always points north.
If not, give them a few minutes with the compass. Have them get in a circle, pass the compass around and have everyone who holds it point in the same direction as the compass needle. When the last student has had a chance to hold it, have everyone look to see where everybody else is pointing. That is north. Make sure to tell them it does not matter which way you turn the compass; it will point north (at least in this experiment!!). And that is because it has a magnet in it.
To shift the focus of this second grade science project back to the magnet itself, ask them to look at the bar magnets. Show them that one end has an “N” on it and the other an “S”. That stands for north and south. The “N” is marked N, because a compass needle will point toward it if it gets close enough. We could also use it to make a compass if it were small enough.
Give two or three students in each group a different magnet. Ask each to try and pick up just one paperclip with it. Then see if any can pick up another by only touching the end of the paperclips together. See who can make the longest chain of paperclips and make sure they understand the reason one magnet can pick up more than another is because it is stronger. Also let them know that the magnet has turned the paperclip it just picked up into a magnet as well. The next paperclip it picks up has also become a magnet, but weaker. Sooner or later one of the next paperclip “magnets” in our second grade science project will not be strong enough to pickup any more.
Give the students some time to play with the magnets and paperclips. Make sure everyone gets a chance to pick up a few paperclips. Then, take one of the magnets, pick up as many paperclips in a chain as you can while the students all watch and be sure to tell the whole group again what they should remember about the experiment (same as in the paragraph above).
While they are all watching, raise the paperclip chain up so all can see. Ask them what they think will happen if the magnet is taken away. (Part of the purpose for any second grade science project is to make a prediction, then test to see if it holds true).
Hold the paperclip that touches the magnet with one hand and remove the magnet from it with the other. Does the chain of paperclips stay attached? No – they will all fall off. Tell them this is because each of the paperclips were only temporary magnets. They were only “magnetized” when they were touching a real (or permanent magnet).
Bring out the strong magnet you put aside for a few days and show the students in this second grade science project the paperclips it has been holding. Take the paperclips off the magnet, and one-by-one, connect them together, just like before to show that this magnet will pick up a chain of several paperclips too. But this time things will be a bit different. Take one of the paperclips off the strong magnet, hold it up and ask the class if they think this paper clip will pick up another one all by itself. To make the point even clearer, take one of the paperclips from the last experiment off the desk and try to pick up another one from the desk all by itself … see, nothing happens.
After they decide, lay the same paperclip flat on the strong magnet and rub it back and forth against the magnet at least 30 times. Now try to pick up other paperclips. It works! Use a paperclip that was on the strong magnet for a couple of days to pick up another. It works too! They should be surprised and will wonder what just happened … now you’ve got them!
Tell them to cover their ears, put one of the magnetized paperclips on the table (or floor if you prefer) and strike it sharply with a hammer. Now try to pick up another paperclip that was not on the strong magnet with it. It doesn’t work any more. The same paperclip will no longer pick up any others!
What are Your Observations?
For the teacher – individual grains in the paperclip have magnetic fields all their own. The longer they are placed in a stronger magnetic field, or are “cold worked” in a magnetic field, the more likely their fields are to align, or point, in the same direction. The final result is that most of the individual field strengths add together and that paperclip’s overall magnetic field is now strong enough to pickup another paperclip. In other words, the first paperclip has become magnetized. When you hit the paperclip with a hammer (or heat it up too much if you have time to try that as well), the temporary alignment that was forced by the stronger magnet is destroyed and the individual magnetic fields start canceling each other out again. In other words, it looses its ability to pick up paperclips.
For the students – we can turn a paperclip into a magnet by having it touch a strong magnet for a long time, or by rubbing it against a strong magnet several times. Our second grade science project shows that it has become a magnet by using it to pick up other paperclips all by itself. (Let them try to pick up paperclips with the magnetized paperclips if you have time). It stays “magnetized” after the other magnet is removed because the metal that makes up the paperclip has tiny “magnets” in it that will all try to point in the same direction if you let it touch the big magnet long enough. But, if you hit it with a hammer, the tiny magnets are shaken back into pointing in different directions again. It is no longer magnetic and just returns to being just another paperclip again.
Summarize by answering the original question: Can we make a magnet?
… and if you don’t have magnets, these are some nice kits you can get:
Now that you can build a magnet, why not build a compass too? http://how-things-work-science-projects.com/how-to-make-a-compass/
This second grade science project is designed as a follow-on to the make a magnet experiment above. We show how to make a compass out of common everyday items, and continue introducing young students to the concept of magnetism.
Strong Bar magnet
Small block of Styrofoam
Small cork, cut so it will float with the flat side up
Plastic or glass bowl large enough to hold the Styrofoam
About a pint of water
The only preparation needed for this second grade science project is to collect the materials in advance.
Gather everybody around the table you will use for the demo. Tell them in this second grade science project, we will see if it is possible to make a compass.
(If you have not done a compass experiment yet, now might be a good time to take the compass out and show them how it works. A very basic project is available at What a compass does if needed.)
When ready, put just enough water in the bowl so that the Styrofoam will float without hitting the bottom of the container. Balance the bar magnet on top of the Styrofoam and watch what happens!
The “N” part of the magnet will point North. Get the actual compass out. Keep it well away from the magnet or the compass won’t point in the right direction … and show the students what the compass says is North.
Now carefully pick up the bowl of water and try to move around so that the “N” part of the floating magnet points in a different direction. Be sure to let the students see that no matter what direction you turn, the magnet will point North. And … that is precisely the point. We just made a compass out of an old magnet, a bucket of water and some old left-over piece of styrofoam! (Kinda like what MacGyver would do?).
Now take one of the smaller paperclips and unfold it so you have one end with a hook and the rest as a straight piece of wire. Rub the end of the paperclip (without the hook) against the magnet back and forth at least 30 times. Rubbing only about ½” on the end of the paperclip should do just fine. Make sure you magnetized it by trying to pick up another paperclip. Rub it on the magnet again if it appears to be too weak.
When the wire is magnetized, continue on with this second grade science project by carefully balancing it on the flat cork, then float the whole works in the bowl of water.
It will be slower this time because the magnet is not as strong, but you should see the straight end of the paperclip heading toward North.
What just happened?
For the teacher – The final result for this second grade science project is that both the magnet and the magnetized paperclip try to align their magnetic fields with the earth’s, but the force of friction on the table top acts like glue to keep them from moving. However, when we float these on water, they are able to move freely. When they do that, they point North. If they always point North, we have a compass!
For the students – A magnet “wants” to point North all the time. When we float it on the water, (hang it by a thread, balance it on a pin point, etc), it is free to move like it wants to. When that happens it points North. When it does that all the time, we have a compass.
Summarize by answering the original question: Shouldn’t we be able to make a compass ourselves?
If you need magnets, these kits can help:
With an attraction to magnets and compasses, build both with this project: http://how-things-work-science-projects.com/make-a-magnet-and-compass/
Kindergarten science projects? I know it’s early, but I also realize kindergarten is a wonderful age of discovery – not so much on the why of it, but the “wow” of it all. Remember?
If not, all that is needed is to watch your preschool age son, grandson, daughter or granddaughter for about 5 minutes (or the ones next door if you don’t have any yet). Youngsters get excited about learning new things. And it is refreshing. Just look through their eyes and be young again …
I know we can’t get too detailed in kindergarten science projects with how or why things work, but we can sure wet their appetite to want to know more. If we can just keep them excited about learning new things … who knows where that will lead?
Here are a few kindergarten science projects to help do just that. Have fun!
Just what is it that a compass does? Will it always point north? Can we convince it to do otherwise? If so, how … and why would we be able to do that?
These are some of the questions this kindergarten science project is designed to answer. It is specifically designed for very young students, but as you will see from other experiments on this site, it doesn’t take much to expand the topic to about any grade level desired.
Enjoy! (and please be sure to let me know how they did!)
Compass Kindergarten Science Project
To introduce young students to the concept of magnetism by using everyday items they are most likely already familiar with.
Magnetite (if available)
No advance prep, other than gathering the materials is needed for this kindergarten science project.
Ask the students if anybody knows where “North” is. Let the discussion happen, and then ask how can we find out if we do not know. If nobody knows, ask if anybody can tell you what a compass is, and if it could it be used to tell us where north is. Again, let the comments come freely, and then have them each look at a compass to see where the needle points in their classroom. If you have enough for a couple groups, ask each group to point to where their compass needle is pointing. They will be able to see that everybody is pointing in the same direction … and that must be where North is.
Then be sure to explain that the way to use the compass is to turn it until the “N” is where the needle is pointing. Yes, that is North, but now the compass will also show you where East, West and South are as well. This can be a fun game to play by itself, where each group has a compass, a direction east, west, north or south is called out and each group takes two steps in the direction called. Many versions of the same game can be played (or kindergarten science project here), but all are fun ways to learn directions and just a little about magnetism.
Now for the second question … do they always point north? This time, have the students identify where north is again with their compass. Place the compass on a desk or table and turn it again so that the letter “N” is in the direction of the needle. Have one person slowly move the magnetite or bar magnet toward the compass and ask them what happened? If you are using a bar magnet, tell them the red end usually has an “N” stamped on it and ask if anyone can tell you why. Yes, it is marked “N” because it is the “North” end of the magnet. A compass will point to the north end of the magnet if they are close enough together. That must mean that the earth is really just one big magnet, and the compass is pointing to the north “pole” as well. Since it does, we can use it to help us find the direction we need to go if we are lost or trying to follow a map.
If the class is especially perceptive, you can increase the depth of this kindergarten science project by turning the bar magnet around so that the “S” points toward the compass. Watch the needle spin away from it. Tell the students the arrow is trying to point away from the magnet because we are showing it the south pole side. If we pretended it was the earth’s south pole, then the arrow would still be pointing to the north pole. Make a big circular loop with your arm from the “S” on the magnet, as if you are drawing a circle around the earth and end up at the “N” to show the needle really does point “North”.
Summarize by answering the two questions: What does a compass really do; and, will it always point to the direction north?
For more fun projects with magnets, these kits can help:
Want to try making a compass? Try this project: http://how-things-work-science-projects.com/how-to-make-a-compass/
The previous project shows that a compass needle can be moved by a magnet (table top version or the earth itself), but what else will a magnet attract? Will it pick up paper clips? A piece of paper? How about chalk?
I certainly agree, it is too early to discuss concepts like electron spin, as is done on the magnet science projects page, but it isn’t too early to help them understand not all things are the same, and that we just might have to try an experiment to be certain what will happen. That is the focus of this kindergarten science project.
Here we go …
Magnet Kindergarten Science Project
To introduce young students to the concept of magnetism by using everyday items they are most likely already familiar with.
small washers (as in nuts, bolts and “washers”),
small pieces of paper, chalk, popsicle sticks, pieces of a plastic cup, etc.
Bar Magnets, one for each group.
No advance preparation, other than gathering the materials is needed for this kindergarten science project.
Ask if anyone has used a magnet before. Let the students give as many examples as they can, but if the discussion goes a bit slowly, help them start by asking if anybody has a refrigerator with magnets on it. They might be letters or numbers or just a small square mom or dad uses to hold up a piece of paper, a picture you colored or maybe even a photograph of grandma all by itself (at least without the need for glue or bubble gum!). Then ask if they would like to see what magnets can do right now!
If you have some additional adult help, break the class up into as many small groups as you have magnets and samples for. While the class is getting into their groups, place different test samples on several desks or tables around the room.
At this point, please let them know that anytime we do a kindergarten science project, we need to set some lab rules. For today’s project, only one person can touch the magnet at a time, and for now, the only thing they can use to pick up the items on the desks or tables with is the magnet. Let them know we cannot use our hands because we are trying to see what will stick to the magnet all by itself.
When they get to their stations, ask them to look toward the blackboard, and one item at a time, write down the item on the blackboard, tell them what it is and ask them to raise their hand if they think the magnet will pick that item up. If most say yes, put a check by it. If most say no, put an X by that item. Now the fun starts.
Hand out one magnet to a student in each group. Have each group gather around their desk or table and ask the person holding the magnet to try to get the paper, or washer, etc., to stick to the magnet. In fact, let’s see if anyone can pick the item up off the desk by just touching it with the magnet. No fair using hands!
It is important to let every student hold the magnet at least once, but if you have limited time, it is not necessary for every student to try picking up every item on every desk. When at least two or three have had a chance to try the magnet at one station, have them move (I’ll say orderly with a smile here) to the next station.
When each group has tried each station, have them put their magnets on the table and look toward the blackboard again. Starting from the top of the list, tell them what it is and ask by a show of hands if it will stick to the magnet all by itself? I’d be willing to bet a fair amount that not all hands will go up or down when they should. But that is ok. In fact it is most welcome.
When the answers are not correct (or you suspect most are just guessing), have the group with that item on their table try to pick it up with the magnet while everyone else watches. That will help tie things together. They don’t even have to know they are learning to hypothesize, test and analyze, but they’ll get it just the same … and have fun doing it at the same time.
Summarize by letting them know they guessed at what they thought would stick to the magnet, and then did an experiment to see if they guessed right. After we did the experiment, we found that only metal things can be picked up by a magnet, not paper or plastic or chalk … etc.
Want to try making a magnet? Here is a project to try: http://how-things-work-science-projects.com/how-to-make-a-magnet/
And for a whole series of other age 2-7 early leaning curriculum, see …
A potato battery project is the last in a series of fruit and veggie battery projects included on this site. Many versions are available, but unless you want to get fancy with the voltmeter, fruit batteries make great science projects for kids since they are both inexpensive and relatively easy to perform.
A quick look at the lemon battery experiment will show it is the same science project, except that we use a potato here. As noted in that project, a fruit battery isn’t powerful enough to light a regular bulb.
A light emitting diode, (LED), could be used to show the effect since it requires much less voltage to illuminate. However, since the room needs to be very dark to see the LED light up, I selected the voltmeter method instead. In either case, it’s listed as a 5th grade science project if performed by itself. If demonstrated along with the “Turning on a Light Bulb” experiment, it could easily be used in elementary science projects from about the first grade on.
With that said, let’s make a potato battery …
We only need a potato, a couple nails and a piece of wire to make a potato battery. It’s a fun science project that helps show the way things work in a battery by using everyday items we see around the house.
As in the lemon battery the goal is to learn more about electricity, and possibly a few new science terms along the way. The project is designed to be performed on its own, but if the “Light Bulb” experiment is done at the same time, it can help connect the concept of a voltmeter reading to the familiar lighting of a flashlight bulb.
– 1 potato
– 3 to 4 in. copper wire with the insulation removed, #12 or #18 is ok, (a copper penny works too)
– 1 steel nail, #6 or 8 is good
– 1 zinc plated nail, #6 or 8 works fine
– Small piece of sand paper
– Wire pliers or a knife to remove insulation (not shown)
– A voltmeter that can read to at least tenths of a volt
To prepare for the potato battery project, simply gather the materials, remove insulation off the wire and lightly sand the nail ends so they will interact well with the potato.
Since the lemon and potato battery projects share the same steps, general concepts and “how it works” explanation, not all of that project info is repeated here. Major steps are listed, but please refer to the lemon battery experiment if more details are needed to conduct this lab.
Split the class into smaller groups as materials allow. If you plan to demonstrate the light bulb project at the same time, show how the battery makes the bulb light up. Shift focus from the light to the meter by showing that the meter moves if its leads are touched to the ends of the battery as well. Then ask … if we can make the meter move by connecting it to the potato instead of the battery, will that mean the potato is acting like a battery too? Let them know the correct answer is yes, assuming that really happens.
The nails and wire will be our test terminals for the potato battery. It does not matter which you start with, so pick any two to begin the experiment. Insert the ends about an inch deep into the potato and get them as close as you can without touching each other. (If they touch, no voltage difference will show and the meter will not move. If this happens, the battery is said to be ‘shorted’. Just pick a new spot on the potato and trying again).
Put the voltmeter on a DC setting. As an optional step, test the voltmeter on an actual battery (C for ex.) if you have one handy. Although not a necessary step for the project itself, it is a good time to discuss polarity if class schedule permits. It is easy to see which terminal is the cathode (+) and which is the anode (-) on a battery because they are stamped on it. By looking at the voltmeter display and swapping the red and black leads from one end of the battery to the other, you can show how the meter displays a minus sign one way, and not the other. This information can then be used to determine which of our test terminals acts as the cathode (+) and which is the anode (-).
Touch the red and black meter leads to the test terminals in the potato battery. (I tried steel and copper first). Take note of the reading, but don’t get too concerned if the values each group sees are different. Readings will probably vary from setup to setup, and from trial to trial. There are a few variables we can’t control with this setup, but getting a voltage reading at all … and noting the relative values of the readings as we try different terminal materials is what is important at this point.
Shift to another terminal combination. Zinc and steel are shown to the right. Again, note the voltage. Higher? Lower?
Try the final terminal set. As in the lemon battery project, you should see why zinc and copper make good terminals.
Take the voltmeter leads off the terminals and hold them apart. Note that there is no meter reading. Touch the leads themselves together. There is still no meter reading. Try poking the ends of the leads directly into the potato without touching the test terminals. Note again that no meter deflection occurs. A meter deflection only occurs when we set up the potato battery in one of the arrangements shown above. We need two dissimilar metals as the battery terminals, and they must be inserted into the potato for the battery to work.
Share with the group that what makes a flashlight bulb light up is the same thing that makes the meter move. It is called a voltage difference.
What just happened?
For the teacher – please see the lemon battery project for a detailed discussion of what’s happening. It is the same process that drives the potato battery. For more information on the theory behind the process, please see the Electricity Science Projects related to Charge section of the electricity page. PS – try raw first, then boil the potatoes and try it again to see what happens.
For the students – if the right metals are picked as battery terminals, a potato can in fact be turned into a battery.
To summarize, tell the group that even though the voltage in a potato battery isn’t strong enough to light a flashlight bulb, it really is the same process that makes a store-bought battery work.
And if you don’t have a multi-meter, or just want something more out-of-the-box for quick demonstrations, here are a few that should do that for you.
Here is another tasty battery project to try: http://how-things-work-science-projects.com/apple-battery-project/
Making a lemon battery is one of the classic science projects for kids. It is inexpensive, easy to set up and fairly easy to perform.
If you take a quick peek at the supplies photo below, you’ll see we need a voltmeter. Don’t let that scare you. A fruit battery doesn’t generate enough power to actually light a bulb, so a meter is needed to see the effect. That’s why I believe this is better suited as a 5th grade science project, if done by itself. However, nothing is hard and fast here. If you want to combine this with the “Turning on a Light Bulb” experiment to bridge the gap between lighting a bulb and seeing the meter move, it could be made to fit elementary science projects from about first grade on.
Enough of the intro stuff … let’s create a lemon battery – and then try to figure out how it works. Have fun!
What could be more everyday than a lemon, a couple of nails and some wire? Well, that’s all you need to make a lemon battery. As is the case with most science projects on this site, the goal here is to learn by using stuff we see around us in everyday life.
We will learn a bit more about electricity, possibly some new science terms, and if this project is done with the first grade “Light Bulb” experiment, we can tie a familiar flashlight operation to the more abstract concept of a meter reading.
– 1 medium size lemon or lime
– About 4 in. wire with insulation
removed, #12 or #18 works just fine
– 1 steel nail, #6 or 8 is ok
– 1 zinc plated nail, #6 or 8 is ok
– Small piece of sand paper
– Knife or wire pliers (not shown) to
– A voltmeter that can read tenths of a volt, but nothing fancy beyond that.
The lemon battery project requires almost no advance setup. Just gather the above material, strip the insulation off the wire and use the sand paper on the wire and nail ends just before performing the experiment.
Break the class into equal groups according to the number material sets you have available. If you are tying this to the battery light project, now is a good time to use the wire, flashlight bulb and battery to show how they are used to light the bulb itself. Tell them we will see if we can make the lemon into a battery like the one you are holding to light the bulb.
Order does not matter, but I selected a steel nail and copper wire to start with. They are our battery terminals. Lightly sand the end of the wire and nail. Without letting any part of the nail touch the wire, insert both ‘terminals’ in the lemon about 1 to 1 1/2 inches deep and as close together as you can get them.
Note – if they touch, our battery will be ‘shorted’ and no voltage difference will be shown on the meter. If that happens, just pick a new spot on the lemon and try again.
Turn the voltmeter on to a DC volt setting. If you have a battery handy (AAA, AA, C or D is fine), use it to show the class that the meter is really working. The meter will show 1.2 to 1.5 volts if new, depending on which you size you used, and possibly less if it is an old one. Let them know that it is this voltage difference that makes the light bulb in a flashlight come on, as well as the lights inside a car, or their car’s headlights at night when they need them.
Note – if the meter shows a minus sign “-” in front of the number, just switch the meter leads (black and red wires) around so that the black wire touches the other end of the battery.
Go ahead and touch one of the meter leads to the nail and the other to the wire. What happens? The reading you see may be different from one lemon to another, and from one trial to the next. This is because the voltage difference we see depends on how far apart the terminals are, how well we make contact with the meter leads, how much and how strong the juice (our Electrolyte) is in each lemon, as well as other things that we cannot easily control in this experiment.
The important thing to note is that there is definitely a voltage difference.
Replace the copper wire with the zinc nail. Touch a meter lead to each nail as shown in the photo. What happened with the lemon battery this time? Same voltage? Higher? Lower?
This time replace the steel nail with the copper wire. Zinc and Copper make great battery terminals. Can you see why?
If you demonstrated the experiment, try to give the students some time to do the lemon battery project themselves. Have them put the black and red leads directly together to show them nothing happens if there is no space between the meter wires. Have them pull the meter leads apart ever so slightly. That will show them nothing happens by itself even if the leads are very close together, but not in the lemon. Have them stick each lead directly into the lemon, close or far apart. That will show them nothing happens that way either. It only works when you have two different materials, close together but not touching in the lemon. But if you have the right two materials, it sure works then.
As a group, let them know the same thing that causes the light in a flashlight to come on is what causes the meter to move. If you decided to do the two projects together, go ahead and reinforce that by turning the light on again. You can even use the volt meter to show how the needle moves when you connect it to a “real” battery.
Then ask what they think would happen if you could hook up a light to the lemon instead of the battery. Now is your chance to let them know a bit about some basic electricity, a few science terms and perhaps even answer a few science questions about how things work.
What just happened?
For the teacher – as noted in Electricity Science Projects related to Charge, a lemon battery provides a potential difference much like in a car battery. Two dissimilar metals are immersed in the lemon’s juice, which acts as the electrolyte. The wire and nails act as the cathode (+ terminal) and anode (- terminal), and similar chemical reactions take place when the voltmeter is hooked up. Ions flow through the electrolyte and electrons flow through the wire.
If the terminals in our experiment are not connected to the meter, no voltage potential can be read. Likewise, if the two metals in the lemon are the same, the chemical reactions do not occur, no ions flow in the electrolyte and no voltage potential is generated … in other words, nothing happens. If we do use the right metals for our terminals, and we connect the voltmeter as shown in the above photos, we will get a voltage reading.
One question may remain … why can’t we turn a light bulb on with this battery? The answer is, even if we connected several lemon batteries together (in series) to get the same voltage as in a D cell battery, the current we can get out of a lemon battery is just too small to light the bulb. But it is fun to try!
For the students – as long as we have the right metals in the lemon, and we connect the voltmeter to each of those metals (battery terminals), we will read a voltage on the meter.
Summarize by letting them know – even though the voltage we see is small and our lemon battery just isn’t not strong enough to turn on a light by itself, it is the same thing that happens in a flashlight.
After the fruit battery series, try the Coin battery project. It’s pretty fun too.
And if you just want something you can pull off the shelf for quick demonstrations, these should help:
Here is another battery project you may want to have fun making: http://how-things-work-science-projects.com/potato-battery/
More fun with electricity for kids!
A coin battery is similar to fruit battery experiments, except that the fruit’s part is replaced by a small amount of salt water. It’s an easy science project to do, especially if a project like the lemon battery has already been performed.
Project supplies are plentiful and you can actually light an LED in this experiment if you stack enough coins together – – – but you have to get the right LED and making it work can be a bit tricky. So we’ll use a voltmeter to show the effect with the coin battery here. This is listed as a 5th grade science project, but if demonstrated along with the “Turning on a Light Bulb” experiment, it can be used in electricity experiments, or elementary science projects from about the first grade on.
How to create a coin battery …
To learn more about how electricity works.
The coin battery is designed as a stand-alone project, but if the “Light Bulb” experiment is performed at the same time, that can help connect what’s happening on the voltmeter’s display to lighting the bulb in a flashlight.
For each coin battery station, you’ll need:
– A small glass or bowl
– Spoon or stir stick
– Thick paper towel, blotter paper or even cloth
– About 6 each, pennies, nickels, dimes and quarters
– Small piece of sand paper
– A voltmeter that can read at least tenths of a volt
– Small battery, AA or AAA is fine
– Optional LED
The only preparation needed for the coin battery project is to gather the materials.
Split into groups as materials allow.
Use the AA battery as shown in the photo to the left to verify you have the meter set up correctly.
If the light bulb project is being performed at the same time as the coin battery, this is the perfect time to show how the battery can be used to make the flashlight bulb light up. Let the students know that if the meter moves using coins and salt water, then they must be acting like a ‘real’ battery as well.
Add a small amount of water in the glass or bowl. 1/4 cup should do just fine. Mix in enough salt such that a few grains no longer dissolve after stirring.
Cut about 8 – 10 pieces of the paper towel or soft cloth into sections that are just big enough to cover a nickel but do not hang over the side. To prevent problems, it is best to use the smaller coin, trace it out on the paper and cut the circles out with scissors. When done, place them in the salt water solution so that you can get them back out one at a time.
Lay out 6 nickels and place one piece of the salt-water soaked paper on each. Be sure that the paper covers the whole nickel, but don’t let it drape over the side. Lay a penny on top of each paper. Be sure the penny touches only the paper or it won’t work well. Each of the penny-paper-nickel stacks becomes an individual coin battery cell.
Turn the voltmeter on to a DC Voltage setting that shows at least one, and if possible, two or more decimal points as shown in the photo. Test each coin battery cell to make sure it is working as a small battery by putting one lead on the nickel and the other on the penny. You should see somewhere between .25 and .50 volts DC depending on how well that cell is working.
After each nickel/paper/penny cell is tested, set it on top of the previous cell. For example, after two cells are tested, you should have a nickel, paper, penny then another nickel, paper, penny. After three cells, you will have a nickel, paper, penny (no paper), nickel, paper, penny, (no paper), nickel, paper, penny … and so on. After stacking each new cell, put one of the voltmeter leads on the bottom nickel and the other on the top penny. With each new added cell, you should see a total voltage that is about the same as adding up what you measured for each individual cell that is now in the stack.
With 5 or 6 cells, the voltmeter should read at least 1.5 – 2.5 volts DC. As can be seen by the photo on the below left, 1.25 Volts were achieved with just 3 cells connected together. After about 3 cells, it gets hard to hold them all together without shorting out the battery. It is easier to build the coin stack on the table and use the points the meter leads to touch the bottom and top coins.
If you would like to take this one more step, 1.4V is enough to light a low voltage LED. You’ll have to be sure the current provided by the coin battery falls in spec with the LED, but give it a try! It’s well worth the effort if you can afford the time.
Try the other coins to see what happens. Make the paper or cloth big enough to cover most of the larger coin, but be careful not to let it fall over the side. You should see that some coin combinations make better batteries than others.
Be sure the students see that if the meter leads are held apart, touched together, or even put in the salt water by them self, nothing happens. Two dissimilar metals are needed to act as the battery terminals, and without them, no voltage is generated.
If you have trouble getting good readings, make sure that the paper does not drape over the side so that it touches other coins. That shorts the battery and little or no voltage will be displayed on the meter. If the water isn’t salty enough, it will not act as a good electrolyte. That means only a few ions will move from one coin to the other and you will have low voltage readings. If you put paper between the individual cells (see above for the correct stacking order), poor if any voltage will be generated.
Those are the most common problems, but if all that seems to be ok and the meter still won’t read, try lightly sanding the coin surfaces with a small piece of sand paper. That should fix it.
What just happened?
For the teacher – except for salt water replacing the fruit, most concepts and “how it works” explanations are the same here as in the fruit battery projects. Please see the lemon battery experiment for a complete explanation of what’s happening in the coin battery. Additional information is also discussed in the Electricity Science Projects related to Charge section of the electricity page.
Where this experiment differs from fruit battery projects is that we connect several batteries together in series to get enough voltage to light an LED. That means we connect the (+) terminal of one battery to the (-) terminal of another.
It is also why we do not put the salt-water soaked paper between individual battery cells. If you look closely, you’ll see doing that connects a zinc-copper battery to a copper-zinc battery. In other words, if you use the wet paper between cells, you will have a (-) nickel terminal connected to a (+) copper terminal, then the same (+) copper terminal is immediately connected to a different (-) nickel terminal when you put the next nickel on the stack. You can think of this as positive voltage going one way, but being immediately cancelled out by negative voltage going the other way. The net effect is no total voltage.
By leaving the wet paper (electrolyte) off between each individual battery cell, there is no electrolyte to force copper and zinc ions to flow. Only free charge will flow from one cell to another through the metal-to-metal contact. When more than one battery cell is included, the voltage increase becomes additive, and you see the effect we saw during the experiment.
This was first performed by Alessandro Volta in something he called a voltaic pile way back in 1800. He used alternating copper and zinc or silver and zinc discs that were separated by cardboard or cloth soaked in salt water, just like we did above. Since some metals have more free electrons to give up or accept in ionic form than others, some dissimilar metal combinations work better as batteries than others. If you tried different coins above, you should have seen that effect. If you tried two of the same coins together, penny – paper – penny for example, you would also see that coins with the same metal in them will not give you a battery at all.
If you wanted to go back and connect several potato, lemon or apple batteries together in series like we just did with the coins, you can see the same additive effect with the voltages. It does not matter what generates the voltage, it only matters that you connect them in series correctly to see the effect. In fact, you could make one battery from each of the above, connect them in series, and you should see a final overall voltage that is very close to the sum of each individual battery cell in the group.
For the students – as long as we choose the right coins for our terminals, and are careful about how we connect them together, we can turn pocket change into a battery.
Summarize by telling the group – each individual coin battery, one penny, one piece of salt water soaked paper and one nickel for example, is too small to light a bulb on its own, but it is still the same process that happens in a battery you buy at the store. We also learned that if we connect enough of the coin batteries together in the right way, we really can turn on a light bulb. It is the same thing that happens in a flashlight, and is especially like the battery in your mom or dad’s car.
Here is a project for those just beginning to learn about how batteries and electricity works: http://how-things-work-science-projects.com/battery-light-project/
First Grade Science Projects
Electricity is fascinating. It is also all around us. We wake by an alarm clock without thinking, then turn on a light and take a shower with hot water that we take for granted. Breakfast is cooked on an electric stove, or perhaps we selected frozen waffles that were kept that way by one use of electricity and warmed for eating by another. We plug in headphones to listen to our ipod on the way to work or school and the lightning bolt of a nearby thunderstorm may be just a mere distraction. It isn’t even something to think about it. It is just a part of our daily lives.
But what if we were to stop a moment and actually look at the world around us? Instead of just accepting that things “are” … could we figure out how things work instead? Could we capture interest long enough to bring a bit of wonder back into the normal everydayness of things? Bet we can, and that is exactly what this group of projects is all about. Given that the audience here is still quite young, most of these first grade science projects have been designed to be heavily supervised by the parent or teacher … but to be freely pondered upon by the young (or young at heart). Enjoy!
Turning on a Light Bulb
Come on – admit it. I know you’ve taken a flashlight apart, looked inside and tried to figure out why the light comes on when you push the button. I bet you’ve even looked at the bulb and wondered how that little thing can make so much light … right? Well, that is the objective here. This first grade science project is designed to help get young students wondering about how things work in the world around them, and then to answer some of those questions to keep them coming back for more. At the same time, it introduces a few concepts about electricity using everyday items they are already familiar with.
– 1 Standard size flashlight
– About 6 in. insulated wire, #12 or #18 works just fine
– 1 magnifying glass
– Small piece of sandpaper
– Pliers to make a loop in the wire (needle nose work best)
– Knife or wire pliers to remove insulation
This first grade science project requires very little setup. Simply remove the bulb and one battery from the flashlight and you’re ready to go. If you want to minimize the time spent setting up in class, you can also strip about 1 inch of insulation from each end of the wire. Make a loop on one end of the wire just big enough to hold the bulb (see photo).
Ask if any of the students have used a flashlight before. Almost every hand will probably go up, but let them give as many examples as they can of when they might need to use one. Then ask if anyone knows how a flashlight works. Chances are that nobody will raise their hand, so ask how many would like to learn, and let the fun begin.
You could break into a couple of first grade science project groups, but at this age, it is probably best to show them all in a single group and supervise while each that want to try can do so. Please be sure to set some project rules like the wire and battery are handled with care and only one person touches them at a time, etc.
If you have not stripped about 1 inch of insulation off each end of the wire and made a small loop in one of the ends with a pair of pliers, do so now. Bend the wire as shown in the above photo and place the bulb in the loop.
Either tape or hold the straight end of the wire on one end of the battery with your thumb and touch the end of the light bulb to the other end of the battery as shown in the next photo. The light should shine. If it doesn’t, either the wire on the battery or the wire on the light is not making a good connection. Use the small piece of sand paper to clean the wire ends … and try again. If you are making a connection (and you are sure the flashlight worked before taking it apart), the light will shine.
Give the students some time to try this first grade science project themselves. Then as a whole group, demonstrate how to make the light work again and ask them what they think will happen if you take either end of the wire or light off the battery. (Part of the purpose for any first grade science project is to make a prediction, then test to see if it holds true).
Take the end of the bulb off the battery. Does the light stay lit? No – it goes out. Tell them this is because an electric current only flows if there is no open space anywhere in our battery, wire and light. This is the same thing as saying current only flows in a complete circuit. When we break the circuit by taking one of the ends of the wire off the battery, (open space now), then current stops flowing and the light goes out.
Then take the bulb out of the wire loop and use the magnifying glass to show them the tiny filament of wire inside the light bulb.
After each has had a chance to see it, explain that when the current flows through that tiny wire, it gets very hot. As it gets hot it glows and that makes the light we see.
To shift the focus of this science project back to the flashlight itself, put the bulb and the battery back in the flashlight. When you turn it on and the light shines, tell them that the button or switch on the side is doing the exact same thing as we did when touched the wire end and the light to the two sides of the battery. The switch completes the electric circuit and current flows through that tiny wire in the light bulb called the filament. It gets hot, starts glowing and then lets off quite a bit of light for such a small object.
It is a bit early to discuss that the light bulb holds the filament in a vacuum so that it does not burn up as fast … but you can include that as well if time allows.
What just happened?
For the teacher – as discussed in Electricity Science Projects related to Charge, the battery provides a potential difference due to two disimiliar metals being immersed in a paste or fluid called an electrolyte. As chemical reactions at both the cathode (+ terminal) and the anode (- terminal) of the battery occur, ions flow through the electrolyte and electrons through the wire, as long as there is a complete circuit. (As an aside, fruit batteries like the lemon, apple or potato, as well as coin battery projects are great ways to focus on the battery itself).
In our experiment, if the light is not connected to one end of the battery and the wire end to the other, nothing happens because there is not a complete circuit for electrons to flow in, and therefore no current flows. When current does flow, the small filament inside the light bulb is a resistance in the circuit, and as current flows through it, it heats up. The type of wire used for the filament is specifically selected for the light it produces as well as how long it will work without burning out (which breaks the circuit and stops the current flow). To keep the filament from burning up too fast, the filament is also encased inside a container (usually glass), the air is pulled out of it and the resulting vacuum is sealed inside it during the manufacturing process.
For the students – as long as we have a complete circle for something called an electric current to flow around, the small wire inside the light bulb will glow. Whether we connect up the battery ourselves, or we put it all inside the plastic flashlight case, as soon as we make the complete circle (or circuit), the light will shine, at least for as long as the battery is good.
Summarize by answering the original question: Can we figure out how a flashlight works now?
And if you would rather try something a bit more “out of the box”, these might help …