The present invention provides interchangeable activity centers having a variety of themes, complexity, or content. Parents, teachers, therapists, or others can select, combine, and arrange two or more activity centers according to a user's interests and capabilities at that time. As the user develops greater skills or begins to lose interest, one or more of the activity centers may be removed, rearranged, or substituted for one or more other activity centers. This may lead to longer interest in the device and better correlate its subject matter with information or materials needed for further development.