What's a Cubelet? Cubelets are robot blocks that combine to work together in a team. Each Cubelet is about an inch-and-a-half across, and magnetically connects face-to-face with other Cubelets. Combine them in different ways, and they'll do different things. Combine them with Legos®, and they’ll do lots of different things. For ages 4 and up. Looking for a challenge? Set your Cubelet robot against a competitor in a contest of battlebots, and see which emerges as the evening’s champion.