Teach Kids About Physics

Studying physics with kids is tremendously fun, and here it’s all about the activities and being hands-on. Kids can begin to grasp many important concepts and develop physical intuition just by experimenting and playing, and grown-ups can help them learn by asking questions: What do you think will happen? What did you notice? Why do you think that might have happened? How about if we try it another way? One crucial thing grown-ups might emphasize through all of these activities is the transference of energy, in terms of potential and kinetic energy. Bring it up over and over again, if you can.

What Kids Will Do

In these explorations, kids might…

  • learn about forces and chain reactions
  • build domino runs
  • build balloon cars (and race them!) and rubber band cannons
  • build spinning balance sculptures from carrots, sticks, and candy
  • experiment with gravity by bouncing balls and crafting marble runs along the walls
  • play with a gravity well
  • discover how to find the center of mass on objects and then balance things
  • launch toy cars into baskets
  • build ramp walkers and race them
  • construct a lever
  • build a salt pendulum
  • experiment with magnets, levitate magnets, and make cereal move with magnets
  • and build a chaotic pendulum

(Designed for preschool and elementary students, though many materials and activities might be of interest to older children and adults, too.)

Read On

  • This Book Thinks You’re a Scientist, London Science Museum and Harriett Russell [Amazon | Bookshop] — I’ve looked at a lot of science activity books, and this one is by far the best I’ve seen. The explanations are very clear, the experiments are interesting but very accessible (and many could be done by children by themselves), and it’s often funny. Highly recommended.
  • Forces: Physical Science for Kids, Andi Diehn and Hui Li [Amazon | Bookshop] — This isn’t mind-glowingly good, but it does a decent job of summing up some very basic physics. We read it several times throughout the week to reinforce what we were learning.
  • Cats React to Science Facts, Izzi Howell [Amazon | Bookshop] — Somewhat amazingly, this won the Royal Society’s Young People’s Book Prize for 2020. It has a modest amount of content, but it has real and clear explanations — real science — and it’s filled with funny cat pictures. My 6-year-old read it back-to-back when she first got it, and I know she’s going to read it many more times. It’s a very silly but pretty effective way to get children reading about science.
  • ABCs of Physics, Chris Ferrie [Amazon | Bookshop] — Although Chris Ferrie’s Baby University books look like baby books, they’re more suitable for preschoolers, kindergarteners, and humans of all ages who might want a simple answer to questions like, “What is diffraction?” or, “What is relativity?” This book doesn’t have answers to all the questions that might come up while studying physics with kids, but it helpfully breaks down some physics concepts into brief and simple terms.
  • My First Book of Relativity [Amazon | Bookshop] and My First Book of Quantum Physics [Amazon | Bookshop], Sheddad Kaid-Salah Ferron and Eduard Altarriba — These books are definitely not for toddlers (as the titles might lead you to believe) — but are marketed to kids 8+ and for kids in high school (and grown-ups). But if you have kindergarteners or early elementary-aged children who loves science, they might devour these, too. They’re great books.

Resources

  • TinyBop Simple Machines app — Another solid minimalist app from TinyBop that allows children to do some brief on-screen experiments with levers, wheels, screws, inclined planes, wedges, and pulleys.
  • Bruce Yeany — Many brilliant science demonstrations (and experiments you can do at home) from the kind of science teacher any child would be lucky to have.
  • Physics Girl — Fast-paced and fun physics videos and demonstrations, with plenty of ideas of simple experiments to do at home.
  • Gravity Maze — A very enjoyable logic game for kids who enjoy puzzles and/or marble runs.

Explorations

Motion and Force

Read: Forces: Physical Science for Kids, Andi Diehn and Hui Li [Amazon | Bookshop]

Chain reactions

Watch: Domino Chain Reaction (Geometric Growth in Action)
Chocolate Dominoes

Activity: Amplification experiment
Set up a chain reaction starting with a small domino and ending with something much larger (like a heavy book). Demonstrate that the domino alone can’t knock over the heavy book, but a chain reaction from the small domino can.

Watch: New Domino World Record + Most Insane Spiral Ever
Cats and Ping Pong Trick Shots
Unconventional Domino Tricks
And: With the above video, replay and stop at various points to discuss why these tricks work.

Activity: Dominoes and Ping Pong Balls (as in the cat video above)
Domino runs are classic children’s activities, and they’re great here for many reasons. They require planning, careful observation, and plenty of fine-tuning. The balls are a great addition, because children have to be careful to make sure there’s enough force both to get the ball moving and to make it knock over the next domino. In the arranged pictured here, we used wooden marble run pieces and Hot Wheels track segments to add some complexity to our domino run.

Activity: Which Door Will the Ball Hit?
Although the video has built-in pauses for you to predict what will happen, you might want to pause it yourself, too, to ask children which door they believe the ball will go through and why.

More Rube Goldberg machines:
Honda: The Cog
The Morning Routine Machine
How to Pass the Pepper While Socially Distancing
The Lunch Feeding Contraption
This Machine Makes a Sandwich and Feeds It to Me

Watch: The Science Behind Jiwi’s Machines
Only the one mini-section linked above (other portions of the video will be linked to below): conservation of energy/kinetic energy section

Activity: Car launch game
Inspiration here. If you have a Hot Wheels car launcher, simply prop a bit of track up with a block, so that when the cars are launched they go airborne. Try applying different amounts of force or moving the target to get the cars to launch into the baskets. (This is a good time to take some slow motion videos!)

Watch: The Science Behind Jiwi’s Machines (simple machines, wheel and axle section)

Activity: Balloon Car Racers
These racers work amazingly well. If you have them, you can certainly use stainless steel drinking straws instead of disposable plastic ones (they both work). Make sure you have a variety of lid sizes, since it’s great to change out the tires and see which ones go fastest. (You might use an assortment of milk or juice lids and lids from Pringles cans, for instance. All of them pierce easily with a bamboo skewer.) Build your vehicles and then race them! Full directions and explanation here.

Activity: Rubber band cannons
With Pringles cans and single-serve soda bottles, kids can make their own cannons, a great way to explore force and energy. The Royal Institution suggests using balled up foil as projectiles, which I recommend also: it can travel a long way but it likely won’t damage anything or anyone. Full directions and explanation here.

Gravity

Watch: Minute Physics: What Is Gravity?
OK Go — Upside Down & Inside Out (music video filmed in zero-g)
OK Go – Upside Down & Inside Out BTS – How We Did It

Activity: Ball experiments

  • First, do the classic gravity experiment: hold two different objects (for example, a big ball and a small ball) and ask the kids which one will hit the ground first. You can try this with a variety of objects after, too.
  • Then get a variety of balls and try bouncing them individually. Formally or informally, measure how high they go. Then try dropping two balls together with the smaller ball on top of the larger ball and observe the results. (Either do this outside or drop the balls in the second part from a shorter height — they really go flying, and you could cause some serious damage!). Experiment with balls of different weight and bounciness and make predictions about what combinations will launch balls the highest.

Activity: Build and demonstrate a gravity well
Here is one clear example of how to use a gravity well in teaching, and here’s another. While many videos recommend constructing your own frame for a gravity well out of PVC tubing, you can get great results just using a hula hoop as the frame. You’ll need a hula hoop, quite large binder clips, and one yard of stretchy fabric (15-20% spandex). Clip it the fabric to the hula hoop, balance it on a series of chairs or stools, and you’re ready. You’ll also want several round weights for the middle. An orange works well for a lighter weight, and an exercise ball (like this 2lb. one) works well for the heavy weight.

Activity: Marble run wall
Create a marble run on the wall using painter’s tape and toilet paper and paper towel tubes cut in half lengthways. Getting the marble run to work successfully will require lots of micro-adjustments and test runs — great practice! — and you can keep it on the wall for many days (or weeks). Just be sure to put a basket underneath to catch the marbles.

Activity: Marble run
Kids can have plenty of fun with the cardboard marble run (above), but if you love marble runs and have Duplo blocks handy, you might consider adding marble run blocks to your set. It gives a toddler’s toy new life.

Watch: What If the Earth Were Hollow?

Balance and Center of Mass

Watch: The Science Behind Jiwi’s Machines (center of mass section)
Activity: Find the center of mass of an object
Have children balance an object, like a ruler or a dowel or a big spoon, on their two index fingers. Then have them slide their fingers toward the center of the object. Their fingers will meet at the center of mass. Try it with objects that aren’t evenly weighted (as a ruler is), like spoons or (carefully, with adult assistance) hammers. Full instructions and explanation here.

Activity: Balancing stick
Have children try balancing a stick on their hand (broom handles or dowels work well for this). Then add a big lump of play dough to one end, a few inches below the tip of the stick (wrapped around). Then have children try balancing it two ways: with the lump close to their hands and with the lump far away from their hands. Which is easier? They can also try swinging the stick in a chopping motion two ways: with the lump near their hand and with the lump far away from them. Is one way more difficult to swing? Full directions and explanation here.

Activity: Balancing sculpture
For this, you’ll need carrots and bamboo skewers (some of them trimmed), along with a variety of balancing supplies, like marshmallows. If you’re having trouble getting a sculpture to balance at all, try shortening the stick between the carrot and the bottle/can support — if it’s too long, it can be quite tricky to get it to work. Full instructions and explanation here.

Friction

Watch: The Science Behind Jiwi’s Machines (friction section)
The Physics Behind The Burj Khalifa And Why It Doesn’t Fall Over
Activity: Friction experiment
Fill a small soda bottle with rice. Tap the bottle to make sure the rice gets packed in tightly. Have kids jam a wooden chopstick down into it. Let go of the bottle and have them lift up the chopstick .The friction between the chopstick and the rice should allow them to lift the bottle by the chopstick alone. Then try the same thing with a metal object (like a stainless steel drinking straw). Does the same thing happen? Why or why not?

Simple Machines

Inclined Planes/Ramps

Watch: The Science Behind Jiwi’s Machines (inclined planes section)
Gravitational Illusions (pause and guess what will happen with the two ramps)
More marble tracks

Activity: Ramp walkers
Make ramp walker toys out of cardboard.

  • For instructions to make ramp walkers out of cereal boxes, see 2:54 in the video, and for instructions to make them out of corrugated cardboard, see 3:30.
  • Ramp walkers require quite a bit of fine-tuning to get them working — adjusting the angle of the ramp and also the curvature at the bottom of the legs (and you also want the legs perpendicular to the body — sometimes you need to pinch them a little at the crease, though be careful with the corrugated cardboard, because too much bending and pinching and it will all go limp).
  • I strongly recommend that you make several ahead of time, so kids can play with them immediately. (Small children will have a hard time sitting through the measuring and the adjusting.) Older children can then practice making their own, after they’ve played with ones that already work.

Activity: TinyBop Simple Machines app
In the inclined plane section of the app, kids can use inclined planes in a pinball-type environment to hit different targets.

Levers

Activity: Lever exploration
Do this activity before watching videos or talking about how levers work, as just by experimenting kids can discover how it works on their own. You can try using a ruler as a lever, with a fulcrum made of blocks, to lift objects, or, if you have it, try using a long piece of wood for the same task, with heavier objects (sand bags, for instance, or a heavy box). Move the fulcrum several times so that they can find out what position for the fulcrum allows them to lift with the least amount of force.

Watch: The Mighty Mathematics of the Lever
The Science Behind Jiwi’s Machines (levers section)

Activity: TinyBop Simple Machines app
In the levers section of the app, kids an move a fulcrum and apply different amounts of force to knock down a castle.

Pendulums

Activity: Salt pendulum
For this activity, you want to create a pendulum from a single-serve soda bottle (or similar object) filled with salt and a length of rope. You might suspend your pendulum from exposed beams in a garage or from a tree branch, for instance. Or you could create a smaller pendulum and suspend it from a broomstick across two chairs.

  • Cut the top off of a single-serve soda bottle and punch a hole in the bottom. Often these bottles are reinforced, but a hot nail will do the trick. This should be done totally by an adult in advance. (What’s important is not that it’s a soda bottle but that the pendulum vessel is tall and thin. Otherwise, the salt will drain from the middle of the vessel quite quickly, leaving a big ring of unused salt around the sides.)
  • Punch a couple of holes in the top of the vessel and attach a length of string. Hang your pendulum.
  • Cover the bottom hole with painter’s tape and fill it with salt.

After this, remove the tape and swing the pendulum. The salt trickling out will create patterns on the ground. You might want to talk about what happens when you pull the pendulum way back, versus what happens when you drop it from a shorter height. You’ll also want to talk about what happens to the period of the pendulum as time passes and why it eventually comes to a stop. For how to create more complex patterns, see this video.

Magnetism

Activity: Is it magnetic?
In this activity, kids will try picking up a variety of objects with a magnet and observe which ones respond to the magnet and which don’t. Set out a big assortment of items on a tray and have the kids predict what will happen with each item. (One particularly interesting item to set out is a pipe cleaner, especially if you have one regular pipe cleaner and one metallic one.) Then get out a magnet and test them one by one. You might consider sorting the items into piles as you test, so that you can talk about what they have in common afterward.

Activity: Temporary magnet
Try rubbing a bar magnet across scissors, for instance, and observe what happens before you rub the magnet across it and after. (As always, be quite careful with the scissors.)

Activity: Magnet Levitation (from This Book Thinks You’re a Scientist [Amazon | Bookshop])
Tie a paper clip to a piece of thread, then put that thread under a book. Use a magnet to levitate the paper clip — and see how far away you can hold the magnet and still make the paper clip levitate. This is a wonderful activity in part because it feels so much like magic.

Activity: Cereal magnetism
Float a Cheerio (or other cereal) on top of a bowl of water and use a magnet to make the cereal move across the water. What makes it follow the magnet? (You might have quite a discussion around this question, and it might be handy to examine the cereal box.)

Activity: Magic Penny magnetism kit
If you’d enjoy doing more magnetism experiments, this kit, which uses British coins (American coins will not work in this context), has loads of experiments you can do with it, including making coins stand up and lie down and making them dance, too. (The instructions for each experiment will likely require a grown-up to interpret, at least for kindergarteners and very early elementary students.)

Activity: Make a chaotic pendulum
Watch: The Chaotic Pendulum
If you have a pack of magnets, you can build one of these personality-filled and delightful chaotic pendulums.

  • For the pendulum, hot glue a magnet to a knot at the end of a piece of string, and then thread the string through a straw and hot glue the straw to the magnet, too (you want it to be pretty rigid). Suspend it from anything you like.
  • For the base, you can simply hot glue magnets to a piece of a cereal box or corrugated cardboard. You’ll want all of the magnets on the base to repel the magnet on the pendulum.

Read On, Grown-Ups



  • Astrophysics for Young People in a Hurry, Neil deGrasse Tyson and Gregory Mone [Amazon | Bookshop] — This book is written for middle schoolers+, but there’s plenty in here to help adults learn how to explain space (and science generally) to kids. Tyson’s writing is filled with humor and relatable analogies, and the book is useful for understanding the Big Bang, the scale of the universe, the elements, and how scientists collect information about the stars. Tyson also writes clearly about dark energy and dark matter. It’s entertaining reading that adults could go through in a couple of hours — and younger children with a passion for space might enjoy going through parts of this book with a grown-up, too. 

This site uses affiliate links. I might earn a small commission if you click through on links to purchase products. I only recommend things I have used and loved.


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s