With the basic Robotist kit from Artec Blocks, kids can easily combine sensors and motors to make their own robot.
The kit contains infrared, touch, light and sound sensors, as well as servos, a buzzer, LEDs, and an accelerometer. With all those parts and a bunch of blocks, there are a myriad of things you can build. Make a line follower, a sun-seeking cat, or an obstacle avoiding car! Plug them in to the included Studuino board, and get coding! The kit works with free software that has three programming modes: a drag-and-drop, a simple operations based environment, and an Arduino IDE.