Light Mixing

Light Mixing

This lesson plan will give students an opportunity to explore how light mixes together.

Duration: 1 hour

Elementary (ages 8-10)



power (1)
rgb led (1)
battery + cable (1)



STEP 1 : Take out your littleBits

Take out the following parts from your littleBits starter kit: battery, battery connector, blue power bit, green RGB led bit.

STEP 2 : Snap them together!

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Put the bits together in the same order as above, so they your completed circuit looks something like the picture

STEP 3 : Use the screwdriver

Turn on your circuit by flipping the on/off switch on the power bit. Take the included purple screwdriver and turn the screws on the rgb led that correspond to red, green and blue all the way to the right (clockwise). While not off completely, this should make the LED dim enough to look at.

STEP 4 : Three Lights

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If you can and it doesn’t hurt your eyes, look carefully at the LED. You should see three little lights: a red one, a green one and a blue one. The diagram here shows a closeup of what your RGB LED looks like if you are unable to see for yourself.

STEP 5 : Red Light

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Take your screwdriver and turn up the red all the way. You should see your LED shine red.

STEP 6 : Green Light

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Take your screwdriver and turn the red back down. Turn up the green all the way. You should see your LED shine green.

STEP 7 : Blue Light

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Take your screwdriver and turn the green back down. Turn up the blue all the way. You should see your LED shine blue

STEP 8 : Mixing Colors, Part 1

Take your screwdriver and with the blue on, turn up the green and watch what happens as you do so. What color do you see now? Is this the color you expected?

STEP 9 : Mixing Colors, Part 2

Turn the green back down. Now watch what happens as you turn the red up when the blue is on. What color do you see? Is this the color you expected?

STEP 10 : A Fourth color

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Turn off the blue, and leave the red one on. This time, turn the green up slowly. (In my experience, if you turn the green LED up all the way, the green will overpower the red and you won’t see the color you should.) As you slowly turn up the green, you should at some point see yellow light! Is this surprising, or is this what you expected based on the rgb color wheel?

STEP 11 : Mixing Colors, Part 3

Based on the color wheel, if you were to now turn up the blue (adding it to the yellow), what color will you get? Try turning up the blue and see if you are right. (Like with green, the blue can overpower the light you are sup-posed to see, so turn it up slowly! If your light starts to look blue, you’ve turned it too far.)