Mathletics Book Recommendations

The books listed below are appropriate for all ages, depending on the mathematical experience of the student. All of them would be interesting to a senior high-school student or adult who is interested in math. Levels 4-5 are subjects normally taught at university. Where possible I have chosen books that emphasize intuition along with rigorous logic.

Level 1

Level 2

Level 3

Level 4

Level 5