# Teach kids (and adults) to master algebra with DragonBox

Lately I've been playing with an app called DragonBox. This game has expanded my mind.

It presents itself as a simple game, with a level structure and game play reminiscent of Angry Birds. The first few puzzles are very easy. Slowly, as the game progresses, new rules and abilities are introduced. And each new rule or ability is oddly specific, maintaining a pleasing kind of symmetry. Every time you solve a puzzle, or master a new ability, there is a satisfying feeling of victory.

Slowly, over many levels the complexity of the rules are increased, but always in a fun and engaging way. And slowly the style and appearance of the elements in the game transform from boxes, critters and dice, until eventually, ever so gradually, they become letters and numbers, and you see that what you have been manipulating all along are equations! Beautiful wonderful equations!

I found this app because I was playing with Tangle. What is Tangle? Tangle is a tool from Bret Victor for creating 'Explorable Explanations', and somewhere in my reading, someone mentioned DragonBox.

I was playing with Tangle, in order to create this minimum price calculator, as part of that damn book I'm still damn well writing.

Building a minimum price calculator was a lot of fun. I finally got all of the ideas about costs clear in my head, ten years after writing my actual first product. Costs. Boring, but crucial. I've done what I can to make them fun. Have a play.

Or if you would rather learn algebra than build a product, play with dragonBox instead.

My book "Choose Your First Product" is available now.

It gives you 4 easy steps to find and validate a humble product idea.