Music. Music teaches you numbers, creativity, patterns, structure, and basically primes your brain for math and creativity in that space. In addition, it teaches you how to think both within a structure and outside the box, as well as the importance of repetition, memorization, and learning a new language.

Music really was my second language, and the ability to read/write it fluently is a skill that takes a long time to master. I really believe that it increases your brain plasticity so much.