CodeBug’s legs are also touch sensitive, so you don’t have to use switches -- you can just use your hands!

• Leave your program on CodeBug from the previous step and make sure CodeBug is powered.

• Disconnect your button from the croc-clips, but leave the croc-clips connected to CodeBug’s legs (1 and GND).

• Hold the metal end of one croc-clip in one hand and touch the end of the other croc-clip with your other hand.

• When you touch the clip, CodeBug senses it and runs the blocks of code you told it to.

This works because everything containing a lot of water will conduct a small amount of electricity. This is not enough electricity to power something like an LED, but it is enough for CodeBug’s legs to sense. Since the human body is about 70% water YOU conduct this small amount of electricity too!

Try holding a friend’s hand and get them to touch the other croc-clip.

Gather some more friends and see how many how people can be in the chain before CodeBug can’t sense the electricity anymore. Each extra person adds some resistance to the electricity in the chain. Each person in the chain adds more resistance which makes it harder for the electricity to flow.