The 5 first Rubik's cubes You would have

In my opinion, I think that is better to know how to solve Rubik's cubes, because the people that know how to solve them get better results in Math tests.

There's a lot of cubes that you can get, for example: 3x3x3 cube, 5x5x5 cube, Megaminx cube, Mastermorphix, 1x3x3 Z cube, and a lot of other cubes.

In Youtube you can find a lot of videos of "How to solve (Name of the cube)" and you can learn how to solve it, and it's easy.

The world's record solving the 3x3x3 cube is 4,22 seconds, and the pyraminx is 0,91 seconds