# Electricity and Magnetism

Compiled By: kristen_teach

Lessons and Ideas to help with a unit on electricity and magnets

Electricity
Posted by: Lauren

We have children build circuits with batteries, wires and lightbulbs. They fiddle around until they figure out how to light it, which teaches them how a closed circuit works. We use the FOSS Science kits which helps with materials, but these things shouldn't be hard to get.
We teach it along with magnetism and children have to create an invention that uses either magnetism or electricity. They also do research of inventors that were important in magnetism or electricity.
I've also done writing with this unit where students write about a time they had a bright idea. Hence, the lightbulb.
This is a hard concept for 4th graders, so I would keep it all pretty basic.

Magnetism and electricity
Posted by: Sharon

Hi! I always start with a book called Mickey's Magnet and then move on to testing objects in the classroom. Students use a recording sheet: does and doesn't stick. Magnets are inexpensive at craft stores. We then make a list and deduce that most metal objects are magnetic etc. I then move on to terminology and demonstrate force, push , pull attract and repel. I tie a paper clip to a chair with thin string and use a magnet to lift it without touching it. This is the force we cant see. I let them feel magnets attract and repel as well. I get iron filings to demonstrate magnetic field by having students move the filings with a magnet under a plate.

I use this to lead into static electricity and use balloons to demonstrate static on hair. The balloons can be charged on the hair and placed together to attract or repel. I use combs and tissue paper to demonstrate static> Students comb their hair and use the static to pick up the tissue. Good Luck

re: Electricity
Posted by: Ann

A simple bulletin board that got my class thinking! It was entitled: Watt would we do without electricity? Each child was given a picture of a lightbulb (asked to color it in ) and asked to fill in the following sentence: If I didn't have electricity I would _______________. Example: If I didn't have electricity, I would read instead of watching tv.

try experiment with induction
Posted by: Chris

This is way late. I'm sorry I didn't see your message earlier. I'm not a teacher, but I have done lectures and demonstrations for classes before with electricity. I'm in college, and experimenting with electricity is one of my hobbies. My mom's a teacher and I've done demonstrations for her class and others. There are a lot of things you can do. One of my favorite, and one that wouldn't be too hard to set up is a demonstration of induction. Wind two coils with 28 or 30 gauge magnet wire. A low voltage battery (from a flashlight will do) is connected to one coil. Connect a 9 volt battery to the other coil, except with a switch to break the circuit. Put both coils around a magnetic "core" - a large nail or even a bolt will work. You will notice that each time you connect and disconnect the battery from the coil, the light bulb will light. But of course, it isn't continuous because the magnetic field has to be moving, so you have to have a pulsating current. The bulb will flash each time the battery is connected and disconnected. You will get varying results, depending on how many turns you have on the coils, the gauge of the wire, and the distance between the coils. You will have to play around with it a little to get the bulb to light. This demonstrates electromagnetic induction, and the principles at work in a transformer. The coils in this little experiment are like the primary and secondary windings in a transformer. You're basically making two electromagnets on the same core, with only one having power.

You can save a little bit of work, if you have an electronics store nearby. Look for a "solenoid coil," preferably one wound for AC. A solenoid is basically just an electromagnet. A lot of common items have solenoids...automatic sprinkler valves have solonoid coils to open and close the valve. For safety, you'll want one for low voltage, maybe 6 or 12 volts AC. If you find a solenoid, you can use that as a primary winding and then you just need to make a secondary. If you do use an AC solenoid, you will need a transformer to step the outlet line voltage down, but you can get one very easily and cheaply. A small 6 volt transformer at Radio Shack was about \$5 the last time I saw. The kids can even try winding different size secondary coils on the "homemade transformer" and see how it effects the experiment. You can get a cheap analog multimeter (\$10 or even less sometimes) and actually measure how the voltage on the secondary is affected by the size of the coil and number of turns. And of course, a multimeter will come in very handy for many other experiments.

There are so many things they could learn from this experiment...

1. Induction - two coils not connected. One is supplied with a pulsating current, and electricity is transferred to the other coil, which is shown by a bulb lighting each time the current is applied and disconnected momentarily.

2. Transformer action - Voltage (and current) can be varied by changing the number of turns on the secondary winding.

3. Frequency - the kids might catch on and understand what alternating current from an outlet (or the "AC mains" as we call it) really is. When we plug a lamp into an outlet, it is actually flashing just like the bulb was in the experiment, but it's flashing so fast that our eyes don't percieve it, so the light seems continuous. They may learn a new term, "frequency," meaning how fast an electric current is pulsating (or in the case of AC, how fast it is changing direction). Common household AC is 60 Hertz, or 60 cycles-per-second.

Electricity can definitely be a very fascinating subject to learn about, and I think 6th graders would be able to understand it. Of course, this experiment is really simplifying things...there are a LOT of other factors that go into a transformer, like things called "impedance," "inductive reactance," "current regulation"...but I definitely won't get into all that here!
:-)

If you can talk to someone who has a Tesla Coil, then you'd really be in business. You can find out more about a Tesla Coil online, but they generate very high voltage at radio frequency and can light up florescent and neon tubes without any wires! I built one a few years ago. A Tesla Coil generates some amazing effects, but they can be dangerous and have to operated by someone knowledgable.

I hope this helps some. Good luck. Try looking on Google for "induction" and "experiments," "school project," etc.

- Chris

bulletin board
Posted by: Julianne

Ok, I think I've got a good one for you. Have each student draw a picture of his or her house and cut it out. Cut out a power station and put half the houses on one side of the board. Then use bell wire (telephone wire or other thin wire will do fine) to connect each house to the next showing a simple circuit. Now cut out another power plant and use the remaining houses in two rows to show a parallel circuit. Do this by having each house link to and from a pair of parallel wires that come down from the power plant. You can see a simple diagram of this in any elementary electricity book. Students can predict what would happen if someone cut a wire in each of the models. If you are handy you can build each of these models using a 6 volt lantern battery for the power source and lights cut from a set of christmas lights for the "houses". Cut each light away from the string leaving two 6" lengths of wire attached. Bare about 1/2 inch of wire at the end of each. Make the simple circuit by joining the lights together in a "holding hands" pattern with the battery at one position in the circle. If any one of the lights is removed the entire string goes dark. To make the parallel circuit you'll need a 1 foot piece of 2X4, 4 nails and about 4 feet of bare copper wire. Drive two nails about 2 inches apart at each end of the board. Cut the wire in half and run each piece between the nails on one side of the board making miniature telephone wires. Leave enough wire at one end to connect to the terminals of your 6 volt battery. Now carefully string your lights by hooking the bare part of one leg over one phone line and the other bare part over the other one. You should have a sort of ladder effect with the lights shining between the two parallel wires. You can show that you can remove any one light and the rest will stay lit.

Boy, I nearly didn't post this...it's so long. But I've used this experiment with kids over and over. It's a real crowd pleaser and they get a real feel for how electricity works.

Magnets
Posted by: Julianne

It is wonderful if the students can fool about with magnets on their own and discover what happens when they try to place the opposing poles together. The wand type magnets are good for this because their field is pretty strong and therefore easily felt. Once someone brings up the fact that if you hold the magnets one way they "attract" and if you hold them the other way they "repel", you can introduce those vocabulary words along with "pole", "north", "south" and "magnetic field". It's nice to have some metal filings to show the magnetic fields, but be careful with the stuff. If kids get it on their hands and rub their eyes or face it can cause irritation. A couple of ways to handle this - You can demonstrate the magnetic field by placing the magnet under a paper plate, then sprinkling the filings into the plate. This is a TEACHER ONLY job in first grade. When you remove the magnet from the bottom of the plate the filings are easily funneled back into their jar. Another way to show the field is to use a plastic sandwich box. Place about a tablespoon of filings in it, then cover it with heavy plastic wrap held down with duct tape. The kids can hold a magnet against the bottom of the container and shake it gently to see where the filings go. Again, watch to be sure they don't break the plastic and get filings all over. You can e-mail me if you want more magnet activities. Have fun!

magnets
Posted by: Amber

First of all collect lots of magnetic and non magnetic items.

Then collect metal trays, tins, boxes, and other containers. these can be used for magnet sorting, testing, and storage.

My roomate made a magnet sensory box with those plastic picture frames that have cardboard box in them. she placed several magnetic and non magnetic objects in each one then each child gets a magnet and the try to pick up magnetic objects. (the box is sealed on after objects are placed inside.)

She also took a soda bottle (plastic) filled it 1/3 full of sand/dirt/water ect... then put shaved metal in it then sealed it. the children take the magnets and run it across the bottle and see what happens.

have children hold two magnets close to each other What happens? Why? have them turn one around then repeat what happens? Why?

Hope this helps

magnets
Posted by: KT

For a source of magnets you may want to look for "cow" magnets. I live in a rural area and at the local feed store they sell some very strong oblong magnets about 3x1". Apparently, cows are made to swallow them and any stray pieces of barbed wire cling to them rather than harming their internal organs. Sounds amazing but true. As far as I know they are still in use and may be an inexpensive source of magnets for various projects.

Simple circuit
Posted by: Julianne

I am guessing about some of this. I have never seen this done with a potato! But I have seen a simple circuit made with a break in the wire that can then be filled with different materials to see if they will conduct electricity. I think the idea of the potato is that it is moist, therefore it should conduct the electricity. Here's how I'd go about this:

1. Get bell wire, a 6 volt lantern battery, the kind with both posts on the top of the battery. These batteries are easier to mess with while still being pretty safe. Be sure you use a flashlight bulb, not a nightlight or other household bulb.

2. Run one piece of bell wire from one terminal of the battery to your bulb's SIDE. Tape or twist it in place.

3. Attach another piece of bell wire from the BOTTOM of the bulb. You can then attach the other end of this wire to the other terminal of the battery to make sure you have a working circuit. If the bulb lights up you know it's working.

4. Now remove the wire from one terminal of the battery and attach another wire there. Take the two unattached ends - one from the battery, one from the bulb - and stick their ends into a small, very juicy potato. If all goes well you should get the thing to light up. If not, then perhaps you could try other materials between these two posts.

Things to try:
aluminum foil
craft stick
wet paper strip
dry paper strip
gold ring
brass ring
nail
button
your finger (yours, not a child's)
ice cube
Christmas tree light

I hope this works for you. Let me know!

Electricity and Magnetism - See your electric company!
Posted by: Amy Bly

Be sure to check w/your local electric company. Depending on where you live they may have free resources, teachers, lessons, etc. The Utility company in my area comes out to teach lessons in grades K - 12. The lessons and resources are always free and always of high interest and excellent quality. I teach in the Everett, WA area and feel very fortunate to have such excellent and outstanding support!

Energy and the Environment
Posted by: Myra

Talking about the environmnetal effects of electricity is a great way to expand the unit. Did you know tha schools spend more on electricity than on computers and textbooks combined. You can also talk about the fossil fuels needed to produce our electricity. You can talk about the problems associated with fossil fuel use (pollution and and the fact they are non-renewable) - bring this to a discussion of solutions (renewable energy and energy conservation). There are some great resouces offered through the Energy Star (www.energystar.gov), US Department of Energy (www.eren.gov), The Earth Day Network (www.earthday.net).

A comprehensive program that can also raise money for your school is offered through the Earth Day Network and Earth Day New York - The Bright Light Energy Saver Fundraiser. Promotes energy efficiency, environmental awareness, and earns money for your school.

The Electric Pickle
Posted by: John Vose

Yes, I have done the Electric Pickle. There is no real risk of fire from it, but you must arrange to be sure nobody touches it because there is household electricity flowing through it.

For anyone who has never heard of the electric pickle:

1. Cut a cord from an old, broken appliance.

2. Separate and strip the ends. Attach each wire to a large nail that you have pushed through an insulator (a large cork works well). Wrap everything with electrical tape to insulate further, but not the pointy ends of the nails.

3. Attach each nail to some sort of vertical support (I use buret holders on ring stands).

4. Push the point of each nail into one end of a large, fresh pickle so that the ends of the nails are about one inch apart inside the pickle.

5. Plug the cord into a regular wall socket so that 110 Volt AC current is flowing through the pickle.

Do this in a darkened room for best effect. The pickle will glow and flash yellow, there may be a few sparks, and smoke will rise from the pickle. The odor is minimal and not too unpleasant. For the few seconds that you will have it plugged in, there won't be so much smoke that it won't dissipate rapidly in a normal-sized classroom. It won't be enough to set off a smoke detector.

John

ENERGY IDEAS
Posted by: JILL

TEACH STATIC ELECTRICITY. ALL THAT IS NEEDED IS BALLON, SALT, PEPPER, WATER TAP.
HAVE KIDS WRITE HYPOTHESIS ABOUT EACH SITUATION. HAVE THEM RUB BALLOON, ON HEAD, MAKE HAIR STAND OUT. HOLD CHARGED BALLOON NEAR WATER, WATER WILL MOVE TOWARD IT. CHARGED BALLOON WILL PICK UP THE SALT AND PEPPER! KIDS LOVE THIS.

I TOO NEED IDEAS FOR PROJECTS! HELP!

Magnet activities
Posted by: JohnV

Some possiblilities, depending on grade level:

1. Experiment by trial and error to find that there are two poles on the magnet and that depending on their combinations, they either attract or repel each other.

2. Put a magnet under a sheet of paper and then sprinkle iron filings on the paper to reveal the shape of the magnetic field.

3. Use a magnet to classify other forms of matter according to whether they are magnetic (i.e. attracted to the magnet) or nonmagnetic.

4. Use wire wrapped around a nail and hooked up to a battery to make an electromagnet.

5. Find magnets and electromagnets in use. They are in speakers and electric motors for example. You can probably get students to bring in non-working appliances and such to be taken apart.

6. Teach how a magnetic compass works.

Hope this helps.

John

magnet experiments
Posted by: Jenn

I teach grade three in Ontario, Canada and we studied magnets earlier in the year. An experiment I did with my students was present them with a problem. (This is done once students have been introduced to the idea of north and south poles). I first gave them two toy cars, two elastics and two bar magnets. The problem they needed to work through is...How can you make one of the cars move without touching it. You must use all of the materials given to you. For that age you may need to prompt or give more direction. Students should be able to fasten the magnets on each of the cars with the elastic bands. Once they have done this, they can use the one car to push the other car away because of the like poles repelling one another. Students responded that their cars were dancing! Very effective to demonstrate repelling.
Hope it works

science help
Posted by: Julianne

For magnets I start by having students handle two magnets to feel the attraction and repulsion. The wand magnets work well for this because they are strong. As a follow-up I have bags of small items prepared. In each baggy are about 20 items. This can be a whole group activity or a center. Either way stress that each object should be tested individually, don't just sweep the magnet in the bag to see what "sticks". I make sure there are a few surprises in the bags, like an aluminum washer, a coin, a plastic toy that has a magnet inside, etc. This way students will guess wrong once in a while and must then try to explain why something broke the rules. A final fun activity is to make a game. To make a fishing game, make a fishing pole of an unsharpened pencil, string and a small magnet. Photocopy fish with upper and lower case alphabet letters (or something else your students are studying). Have students cut out the fish and place a staple in their snouts. Now they can fish for pairs. Or, you can photocopy paperdolls with a base that can be folded under to let them stand up. Now attach a paperclip to their base. you can use a magnet to make them "dance" around on the top of a box or even a desk. (doll on top of the desk, magnet beneath)

For hibernation, it's fun to make a little flap book. Have students study animals that hibernate. Then create the book by drawing a tree, a cave, underground, etc. on each page. Add a flap of brown paper. Under the paper draw the animal hibernating in its den. The student adds an appropriate sentence to make a story - "A fox hibernates in his den. A rabbit hibernates underground. A bear hibernates under a fallen tree." And so on. Another fun activity to do with hibernation is to calculate how many hours a child sleeps in winter, and how many hours a hibernating animal would sleep.

ANother option
Posted by: Heidi

I still remember doing the needle compasss activity when I was a grade 4 student! And it helps me know which way is north in the city when I picture how the school sits and how the needle pointed. We magnatized the needle by rubbing the magnet across it alway stroking away from us, never back & forth. Then we ties thread to the middle of the needle and let the needle suspend. It took time for it to hang still but it worked! It pointed North. The teacher did it as a demonstration, the students didn't each try it.

My grade four class did magnatize nails though, learning to stroke the magnet always away from them. They had great fun dropping and banging the nail to "de-magnatize" it so the next kid in the group could try! We also suspended a bar magnet by string and taped it to the underside of a desk to see if it would eventually have the N end pointing North! It did. The kids like that one too!

discovering with magnets
Posted by: cnm

Something my first graders really loved was getting a magnet and walking around the classroom--discovering what was magnetic and what was not. They can keep a "Magnetic Journal" at a magnet center for the class of the interesting items they find in their classroom that the magnet might cling to (the pencil sharpner, filing cabnet, etc.) The only thing--make sure you have the discussion about not toughing the magnet to the computer!