One of my greatest dreams is getting good musical education and playing jazz and classical music. You know, these kinds of music can only be performed by professional musicians, never by dilettanti, thus in order to play high-class jazz or compound classical compositions one should study for many years, and be creative enough to improvise and arrange tunes. Also, many classical instruments like doublebass, cello, piano, trumpet and percussion are also used in jazz. [I think I'll study playing doublebass in order to perform both classics and jazz ;)]
But these are the only points of similarity between jazz and classics, since classical music is governed by numerous rules of melody and harmony, while the main rule of jazz is breaking the rules of rhythm, tonality and compositions.
I really hope it's not too late to enter a musical academy at the age of 18.