This is what educational gaming should look like: no lecturing, no forced 'learning objectives,' just a well-designed puzzle system that happens to teach real engineering and physics.

Poly Bridge nails the balance between accessible and challenging. Early levels teach the basics (roads need support, hydraulics can lift sections), then the game steps back and lets you figure out increasingly complex scenarios. Bridges collapse in satisfying, physics-accurate ways, and each failure teaches you something concrete about structural design.

The sandbox mode and Steam Workshop elevate it beyond a simple puzzle game—kids become creators, designing challenges for others and reverse-engineering solutions to community puzzles. It's the kind of open-ended tinkering that actually builds problem-solving skills.

The only real downside is that it can frustrate kids who expect instant success or flashy rewards. This is a slow-burn, trial-and-error experience. But for kids (or adults) who enjoy methodical problem-solving and creative building, it's excellent. And the complete absence of monetization nonsense makes it a rare gem in the mobile/indie game space.