Describes an interactive problem-solving videodisc program designed for the middle schools. Explains the interdisciplinary nature of the program that includes information from astronomy, geology, history, and meteorology. Contends that the product is an excellent example of well-designed educational software. (CFR)

Provided is a teacher's guide for a problem-solving activity that establishes a link between number patterns and geometry by focusing on the development of recurrence relations established when generating central polygonal numbers. Reproducible worksheets and a 3.0 BASIC program for the activity are given. (MDH)