MY NERDY NEPHEW grew up on Legos and all the fun (and foot pain) they bring. Now 14, he’s developed an interest in making things that do something. Enter robot kits, with machined aluminum parts, gears, circuits, sensors and intricate programming languages. These kits aren’t just fun, they sate a curiosity for complex engineering better than any Erector Set.

Today’s best schools push STEM—Science, Tech, Engineering and Math—as a basis for understanding careers of tomorrow. Makeblock, a China-based creator of robot kits,...