Robot Education dot org is a group that is looking to evaluate robots for use in teaching kids computer science skills. On their website they have instructions for adaptating of a commercially available robot called Scribbler for use in classrooms. Their adaptations to the robot include adding a bluetooth receiver and a set of programming tools. They call their set of programming tools, MyRO - short for My Robot. The Myro API can be used on top of the Microsoft Robotics Studio software.
The Scribbler Robot is available online. A list of retailers can be found at the Scribbler website. Without the bluetooth adaptation the Scribbler robot kit retails for $100-80.