If it’s two wires, you will probably be able to tell when you open it. Often, you can just rip the two colors apart to make 2 separate wires. If it’s one wire and just has outer insulation that is two colors, that’s totally fine and you can use it as a single wire. Good luck!

Hi! I’m sorry it was unclear! I only showed a picture for bending the wire and attaching one of the leads using the needlenose pliers, but as I explained in the text, you simply repeat this process to connect the three components (switch, motor, and battery) into a circle. The order doesn’t matter. The next time I do this activity with my kids, I will take a few extra pictures of that process to makes sure it is clear. Thanks for the suggestion!

It should absolutely work with AA batteries rather than AAA, but it will be a little heavier, so it might not “wiggle” as much.

That’s a good question! I’m all for using what you already have. The problem with the gear shaft is that you won’t be able to attach the eraser tip to the end of the motor. The eraser serves the dual purpose of 1) causing the bot to wobble and 2) protecting your floor. The motor with the gear shaft should wobble on it’s own without the eraser, but it doesn’t have the soft tip that would protect your floor. I probably wouldn’t use it on a wood floor, but it should be fine on low carpet. Concrete or cement might damage the gears.