Ready to use

Every built tool. Each one is a single file that works offline.

4 tools

Line up a marching band in pairs and rows. Does everyone get a partner? How many ways can 12 musicians march?

Build the pig a house from straw, sticks, bricks, glass and more. Then send in the wolf, the rain and a cold night.

Spin a 3D atom, light up its emission spectrum and wander the whole periodic table. No quiz, just curiosity.

Click a state, name it, fill the map. Practice at your own pace, or take the three-strike Challenge.