Here is another educational kit for LEGO fans. The LEGO BOOST Creative Tool comes with over 840 LEGO pieces, distance/color sensor, motor, and everything you need to get started. Bluetooth support is built-in.
The robot stands over 10-inch tall. You can try 5 models with this (Vernie, Guitar 4000, MIR 4, Frankie The Cat, Auto Builder). Your kids can code their creations behavior using the free app.