Teaching children a thing or two about robots and coding is going to be much easier when you have an educational kid like STEMI. This is a hexapod robot that you can build on your own. The robot can be controlled from a smartphone. STEMI supports complex movements, so it can dance, change height, and play with you. It will have an Arduino compatible board.
STEMI has 2 rechargeable batteries, 18 servo motors, and various aluminum parts. It comes with everything you need to build your own robot. You can find out more about it on Indiegogo.