An instructional device for use by music students is constructed as an outer sleeve having a slide member fitted within it. The outer sleeve has first and second sets of openings through and is imprinted with a representation of a piano keyboard on one surface. The slide member has alphabetic representations of musical notes arranged to show through the first set of openings as the slide member is moved through the sleeve. One alphabetic representation shows the musical key selected and seven others display the notes of the major scale and major and minor chords associated with that key. A first series of markings sized and located to show through the second set of openings and will indicate the piano keys related to the major scale selected. Additional sets of openings and markings on the slide member indicate the piano keys associated with the major and minor chords selected. These piano keys may also be shown by colored markings or differently shaped openings.