1. An instructional system for teaching music theory, said system comprising: a sound matrix grid including at least one two-dimensional repeat pattern of indicia corresponding to the notes of the twelve tone scale, said two-dimensional pattern comprising: C ♯ E G A ♯ B ♭ F ♯ A C D ♯ E ♭ B D F G ♯ A ♭ and a simulative or operative piano keyboard, wherein the keys of said keyboard have indicia thereupon corresponding to the members of the matrix.