Presentation Title: Diffy & Divvy – Two Math Games for All Ages

Abstract: While current state and national mathematics standards emphasize the importance of building number sense and performing arithmetic accurately, it can be difficult to find activities that provide practice with arithmetic operations, while also engaging or motivating students. In 1975, a game called DIFFY appeared in an issue of the “Arithmetic Teacher.” This game is still relevant today, as a motivator for elementary students to perform subtraction with whole numbers, integers, and rational numbers. The presentation will show how the game works and discuss its implementation at various grade levels. Participants will be provided with reproducible DIFFY boards. As an extension to DIFFY, there is another game called DIVVY that can use the same game board to practice division. Extensions of both games to higher level mathematics are possible, and the following questions will be discussed: (1) Can we use DIFFY/DIVVY for practice with operations on irrational or complex numbers or algebraic expressions? (2) Could DIFFY be used in a computer programming course?