The eighth-grade Physics by Design class at the Shady Hill School in Cambridge, Mass., has a reputation for being downright fun. But most students don’t refer to it by its conventional title, they just call it Lego. That’s right. Lego. You won’t find students here nodding off to sterile terms in a textbook; instead, they’re elbow-deep in bins of colorful plastic bricks building cars and movable robotic arms. And because they’re learning to program whatever they build with the help of Robolab software and a microcomputer embedded in a Lego brick, they really understand the meaning of torque, velocity and momentum.