Featured
Math you can see
Ten pictures that make big ideas click: E = mc², the size of the Earth, why a circle is a little more than 3 squares, and the planet found before it was seen.
Status: preservedVault II
Open The Lab
Scientific ideas you can play with. Tap, slide and build until it clicks.
Cosmic Periodic Table
A star, a tree and you are made of the same 118 bricks. Tap every element, build molecules and forge stars.
Status: preservedVault II
Open 
How can a car stick to a vertical wall?
Suction pumps the air out from under a car, so the air outside pushes it into the wall. That push makes friction, and friction holds the car up. Try it in the simulator.
Status: preservedVault II
Open