A little less than a year ago, Sphero released the first edition of its Spark robot, a rolling ball you can control with a mobile app. Since then, the product has been adopted as a tool for teaching kids about robotics and computer programming in over 1,000 schools across the US and Canada. Today it's announcing the second edition, the Sphero Spark, which has a tougher, scratch-resistant skin. It also has a more advanced version of Bluetooth, meant to make it easier to pair the bots with multiple devices in a classroom setting. Aside from these two changes, the new Spark unit is basically identical to its predecessor in size, price, battery life, and capability.