Meet the Robo Wunderkind: an educational kit designed to get your kids familiar with robots and coding. It comes with smart cubes that you can attach in various ways to build fun, smart robots. It not only has a modular design, it is LEGO compatible.
Robo Wunderkind allows you to build your own robot that can be controlled using a smartphone or tablet. There is also a visual programming interface to get kids started faster. Each of the cubes you get has its own function. You get battery, micro-controller, Bluetooth, and other cubes. More information is available on Kickstarter.