Thematic education programs are increasingly common in art museums across the world, especially when it comes to programs for schools. Currently, however, there is no consensus as to what constitutes a valid theme. This article makes explicit four different conceptions of the term "theme" that underlie current art museum education programming. These include: (1) Themes in a literary sense, (2) Themes in the musical sense, (3) Themes in the Modernist sense, and (4) Creative process as theme. Following an explanation of each category, the author reflects on the affordances and limits of each kind of theme for both interpretation and museum-school connections.