This puzzle is rated 3 star (hard).
Here is a class puzzle.
Two white toads and two black toads are sat on toadstools (that can only fit one toad on each). There are 8 toadstools arranged in a square (3 by 3, with the middle empty), as shown above. The white toads are sat in the corners at the top and the black toads in the corners at the bottom.
The toads want to swap places, but they can only jump according to the rules of a knight in chess (that is 2 squares up or down and one to side, or two squares to the side and one square up or down).
Swap the toads positions in as few moves as possible.
Check the solutions page for the correct answer.