Look, we all have that bin of random LEGOs that exists solely to destroy our arches at 2 AM. This book actually gives those bricks a job. It’s not just 'build a car'—it’s 'build a lever that hits a ball that rolls down a ramp to ring a bell.' It’s physics masquerading as play, which is the parenting holy grail.

The only catch is the 'BYO Bricks' factor. The kit comes with the weird specialty parts (the balls, the string, the ramps), but it assumes you have a decent stash of standard plates and bricks. If you don't, your kid is going to hit page 12 and start losing it because they can't finish the 'Chain Starter.' Check your inventory first, then let them loose.