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Simple Circuits Challenge: A Guide to Using Output

Simple Circuit: To complete a simple circuit, you must create a loop for the electrons to flow. Since all inputs on Makey Makey complete a circuit, you just need to figure out how to wire up an LED and build a simple switch. If you build a successful current, your light will shine on any key press! In this lab, you will create your own simple circuit with Makey Makey, building simple switches, and once you've mastered that, you'll move on to parallel circuits.

Objectives and Prep


NOTE: This project was written to be used by teachers as a lesson plan.


  • Introduce the TMI Design process from Invent to Learn - Think Make Improve
  • Complete Circuit Challenges
  • Create simple circuits with LEDs and Makey Makey
  • Create switches with playdoh, paper clips, pennies, and other conductive resources
  • Engage students in simple electronics
  • Entice students to create with technology rather than just consume it


You will facilitate this like a Science lab or stations.

Note on Standards: These lessons were developed with the idea that teachers all over the globe and a variety of grade levels could hack the lesson plan to meet student needs. These are just some of the standards the lessons are based on, and not an all-inclusive list. Many of the NGSS align by grade level, so if you teach 9th grade, you could find the stair-stepped standard by looking at the HS NGSS standards.

Prepare the telephone wires for later use. Or use the white hook up wires in your Makey Makey kit.


Student Makey Makey Challenge Cards

Print out this PDF and cut out challenge cards to hand out to students.

Simple Circuit: To complete a simple circuit, you must create a loop for the electrons to flow. So you need to get power from your power source to the LED and back to the power source. If you build a successful current, your light will shine! In this lab, you will create your own simple circuits with Makey Makey since every key press works by completing a circuit. After you learn how to complete a circuit, tinker with materials to build your own DIY switches. Share this video to give students an intro to the back of their Makey Makey.


Simple Circuit: Challenge #1: Light an LED

Can you figure out where to plug in the LED on the Makey Makey so that it only lights up when you make a key press? Can you use Play Doh to light up the LED? Remember that LEDs have a short leg to indicate the negative side and a long leg for the positive side. You need to create a loop for the current to flow!

Ohm Resistors 

You will need an ohm resistor in your Makey Makey circuit so you don't blow out the LED. To figure out what ohm resistor you need, you have to use Ohm’s Law. That formula is V = I × R, where V is the voltage, I is the current, and R is the resistance.

Check out this table from Evil Mad Scientist.

Makey Makey output is between 4.5 - 5V, so for a Blue, Green, White, or UV LED, you will want to use a 48 ohm resistor. 

If you are using a Red, Yellow, or Yellow-Green LED, you will want a 36 Ohm resistor.


Use this video to show students about the back of the Makey Makey and how to light up an LED with a coincell battery. Explain that they should NOT light up an LED by putting the positive leg into the 5V output as it is too much power for a normal LED. Instead, they are going to use the "Key out" pin on the Makey Makey, so they have to build a switch or close the circuit by hand to light up the LED.

If students struggle with lighting up an LED on a key press, share this video.


Simple Circuit: Challenge #2 : Human Circuit

Can you use people to complete the circuit? Can you add people and the LED still light up? How many people can be in your chain and still complete the circuit?


Try having kids hold elbows, or make a classroom high five! How many kids can you add and still complete your human simple circuit?

Simple Circuit Challenge #3 : Tin Foil Piano

Can you create a Makey Makey keyboard with tinfoil and popsicle sticks? (Hint you will need to create your own piano with Soundplant application or use the makeymakey.com/piano .


If students are having trouble, you can show them how to make a conductive piano key by covering a popsicle stick with tin foil and attaching an alligator clip to a key press. Use this piano app or make your own in Scratch!


Simple Circuit Challenge #4 : People Piano

 Can you create human piano keys? Can play the piano by playing your friends?


This is my favorite one! There is always one student that holds all the alligator clips to create cacophony!

Simple Circuit Challenge #5 : DIY Switch

Can you make a switch with Playdoh that will still light up your LED on the MM without using yourself or another person as a ground.  (Hint: You will need two alligator clips to Earth.)

This is a good way to tinker with conductive materials too. What other materials can bridge your switch?


Simple Circuit Challenge #6 : Parallel Circuit

Parallel Circuit: How can you create a parallel circuit that will successfully light up a second LED? Can you make a parallel circuit with Play-doh? Remember to keep the negative leg of the LED connected to EARTH and the positive longer leg connected to KEY OUT.

Continue to use a key press or switch to light up your LEDs.

Simple Circuit Challenge #7: Parallel Circuits Max

Parallel Circuit: How many LEDs can you power? What ports on MM will allow you to power LEDs? Remember you can use any EARTH input to ground your LEDs.

Try lighting multiple LEDS with Playdoh as your conductor, then try making a parallel paper circuit with copper tape.

Which one is brighter? Why? Does one allow you to light more LEDs than the other?

Simple Circuit Challenge #8 : DIY materials

Building a Switch: What other materials can you use to build your own switch? Try to get as inventive as possible with your materials!

What materials work? Why?

What materials won't work? Why?

How could you use materials that aren't conductive to build more complicated switches?

Write your own Code in Scratch!

Teach your students how to trigger events in Scratch with the "When key pressed" block, then delve further to see how you can make your own games and your own controllers!

Here's a great guide to help get started with Scratch



Time Investment
1 - 2 hours
Pre-K - 12+


  • Makey Makey
  • Printed and mounted giant Makey Makey
  • Aluminum foil
  • Cardboard
  • Masking tape
  • Copper brads
  • Canary cardboard scissors
  • Wire strippers
  • Heavy duty knife
  • Hook up wire

EDU Standards

Next Generation Science Standards

Grade 4: 4-PS2 (Energy), PS3.C (Relationship Between Energy and Forces), PS3.B(Conservation of Energy and Energy Transfer), MS-PS3-5(Construct, use, and present arguments to support the claim that when the kinetic energy of an object changes, energy is transferred to or from the object.), PS3.B(Conservation of Energy and Energy Transfer).


Download PDF copy of this Guide



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