The invention provides a device for music theory comprehension. The device includes a base portion and a first stencil. The base portion includes a plurality of marks. Each mark includes indicia representing a musical note. The first stencil includes a first interior shape, wherein the first stencil and the base portion are selectively positionable relative to each other. At each of a plurality of predetermined positions determined by the plurality of marks, the first interior shape of the first stencil surrounds multiple marks. The multiple marks include indicia representing seven musical notes representing a unique chord family.