"mathematics. It is every bit as mind blowing as cosmology or physics (mathematicians conceived of black holes long before astronomers actually found any), and allows more freedom of expression than poetry, art, or music (which depend heavily on properties of the physical universe). Mathematics is the purest of the arts, as well as the most misunderstood.
http://www.maa.org/devlin/LockhartsLament.pdf
Please read this long but enjoyable and very thought provoking essay from Paul Lockhart - it will change your idea of what education should be."