We've got a bunch more in the pipeline. Stay tuned for periodic Cubelet launches, or suggest an idea for a new Cubelet in the forum.
The Getting Started Guide should give you a few ideas on how to begin building.
Check out the Cubelets lesson plans, educator pack, reading list, and events schedule on our Education Page.
The Modular Robotics Forum has a lot of answers. If you're stumped, drop us an email at email@example.com.