Introduction: Easy Arduino "Decision Maker"

In this Instructable, I will be teaching you how to make a "Decision Maker" using Arduino.

My topic would be "What To Eat For Breakfast".

This "Decision Maker" will automatically select the provided options (through shining LEDs) when the lights are on; when the lights are off the LED will not be shining.

*The materials, code, and videos are provided below*


  • 1 Arduino Board (any type)
  • 1 breadboard
  • 6 LED Lights (any color you like)
  • 6 Resistors (1/4W)
  • 1 Precision resistor (1/4W)
  • 1 Photoresistor
  • 20 Lines
  • 14 Crocodile Clips
  • 1 Tissue Box
  • 1 Corrugated Fiberboard (Plastic)
  • 1 Colored Paper (B4)
  • 1 Screwdriver
  • 1 Scissor
  • 1 USB Line
  • Tape
  • Double-Sided Tape
  • Glue

Step 1: Creating a Photoresistor Circuit

To create a photoresistor's circuit, connect the positive and negative charges from the breadboard to your Arduino first. Then place the photoresistor on the breadboard, one leg placed in the positive charge, then connect the other leg with the precision resistor with a line. The precision resistor should be connected to another line, which leads to the analog pin (in this case A0).

Take a look at the circuit diagram, to have a clearer view of the photoresistor circuit.

Step 2: Creating LED Circuits

You will need 6 LED lights, 12 lines, and 6 resistors in this step.

Place the LED light onto the breadboard, connect the positive leg with the positive charge on the breadboard. For the negative leg, use the resistor to connect to the negative charge of the breadboard. Then, connect the positive leg with a digital pin (each LED light has to have a different pin). Repeat this step for all of your LEDs.

Take a look at the circuit diagram, if you are having trouble creating your circuit.

*The circuit for each LED light is the same*

*You don't need to have exactly 6 LEDs, you can decide how many options (which is the number of your LEDs) you want to have in your "Decision Maker"*

Step 3: Entering the Code

To get your circuit working, you have to insert the code into the Arduino app.

The code is in the link below, you just have to copy and paste it into the app, then change your pin numbers if it is different than the ones in the code.

Code Link:

Step 4: Testing Your "Decision Maker"

Before decorating your "Decision Maker" be sure to test it.

After creating the circuit and adding the code, plug your USB line, and test your circuit!

Your "Decision Maker" will look something like the one in the video below but without the box ;)

If your "Decision Maker" has some problems, try double-checking your circuit and your code, to see if you have a tiny mistake!

Step 5: Decorating Your "Decision Maker"

To decorate your "Decision Maker," you can choose to download my printouts, or create your own!

My topic is focusing on "What To Eat For Breakfast," if you want to print it our, the document is available below.

Now, you will have to find a box that fits your breadboard and Arduino ( any box that fits your breadboard and Arduino will be fine). Cut your box open and poke some hole on the top of your box so that the photoresistor and the LEDs are able to be seen. Cover the top of your box with some colored paper and glue on the pictures you just printed out. Use crocodile clips to intend your LEDs and photoresistors so that they appear on top of the box. You can also use plastic corrugated fiberboard if needed. Glue your box together after everything is set. Be creative with your decorations!

Step 6: You Did It!

If you finish all the steps above, congratulations, you made a "Decision Maker"

It might look like the one in the video below, or maybe even more fascinating!

*You can try it out in the dark, and see if it works when the lights turn on*