STEM for Kids: Make Your Own Calculator

Who doesn’t love a light to turn on when you figure out the right answer? Today I am going to show you my all time favorite experiment when I was a kid.

When I was in 4th grade, we were challenged to create a game to make learning math fun.  In my 9 year old opinion this was the coolest math game ever because my mom and I made our own calculator using aluminum foil and a circuit set with a light. Check this out.

What you Need:

  • These printable (editable) math circuit cards found —>here <—
  • Strips of aluminum foil
  • Tape
  • Hold punch
  • A circuit set that includes a light, battery, and two connecting wires. I used the circuits from our Snap Circuit box. You can also find ones here on Amazon.

How you do it:

  • Print a math circuit card on cardstock
  • Punch holes next to each equation and answer
  • Fold the card in half
  • Draw a line connecting the math equation with the right answer using a pencil
  • Tape strips of aluminum foil over each line. (Make sure you fully cover the foil with tape)
  • Test out each circuit you created!

What happened: Aluminum foil is a material that can conduct electricity meaning electricity can flow through it. In this case, it will close the open circuit and cause the light to turn on.

Allie loved making up her own math circuit card light up and recreating a memory for her ol’ mom! What memorable science challenge do you remember as a kid? I’d love to hear about it in the comments below!

Have fun making memories!


Categories: how to videos, STEM Tags: , , , ,
What is static electricity?

balloon!One cold day, Allie walks up to me with a big smile and shows me a balloon that was sticking to her shirt from static. I smiled, took the balloon, rubbed it in her hair, and made her hair stand up. She thought this was pretty neat.

Then I attempted to explain that her hair was standing up because of static electricity.  This happens when the balloon is rubbed on her hair and builds up a negative charge of extra electrons.  I got a glazed over look.  So I thought I would  explain static electricity another way.

Question:  What is static electricity?

Plan:  Static electricity is so powerful that it can not only make your hair stand up but it can make running water move.  We went to the sink and turned the water on to a trickle. Then I gave the balloon another good rub on her hair.

Her guess: (This is when I asked Allie what she thought would happen.) She assumed the water would stick to the balloon. The results even impressed me – you can tell from my reaction!

What happened: When the balloon is rubbed on your hair it builds up a negative charge (of extra electrons) and your hair has a positive charge (from losing electrons).  Positive and negative are opposite and opposites attract. In the case of the water, the negative charge of the balloon is so powerful that it can make water molecules move toward it!

Follow up:

Frizz Control

After that experiment it got me thinking about how to control hair frizz. Poor Allie doesn’t need a balloon rubbed on her head to have static in her hair. So I bought some anti-frizz product. But why does this keep away static?

Dryer Sheets

Then I remembered you can use a dryer sheet to keep your clothes from sticking to you when you are already wearing them. I never seem to have one when I need it. Was there something the same with a dryer sheet and anti-frizz products?

Positive charge ingredients!

Turns out there is! They both have ingredients with a positive charge that cancel out the negative charge of static buildup.  Dryer sheets have fabric softeners to provide a positive charge to cancel out the negative charge of electrons when clothes spin in the dryer.  Anti-frizz products have similar positive charge ingredients that cancel out the negative charge on frizzy static-y hair.

Isn’t science amazing and it’s in our everyday life!

Hazards of static electricity

All of this static talk got me thinking of this video of how static electricity and pumping gas are a dangerous combination. The woman in this video is wearing a sweater which has built up static electricity after getting in and out of her car. When she goes to remove the gas nozzle something scary happens!

There are gasoline vapors that come out of the nozzle when you are pumping gas. If you are charged with static electricity and touch something metal a spark will happen. If there is a spark around that vapor, it will ignite.

So remember, the best way to avoid this is don’t get back in your car when pumping gas and if you do, touch something metal by your driver’s side car door before you go to remove the nozzle.

I hope you enjoyed the post!  Have a great week and be safe!


Categories: 3 ingredient experiments, 5 minute experiments, how to videos, lovely conversations Tags: , , ,