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 and is imprinted with a representation of a piano keyboard. The slide member has alphabetic representations of musical notes showing through the first set of openings as the slide member is moved. One alphabetic representation shows the musical key selected and seven others display the notes of the chromatic 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 will indicate the piano keys related to the chromatic 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 shown by colored markings or specially shaped openings.