Reinforcing Key Combinatorial Ideas in a Computational Setting: A Case of Encoding Outcomes in Computer Programming

Counting problems are difficult for students to solve, and there is a perennial need to investigate ways to help students solve counting problems successfully. One promising avenue for students' successful counting is for them to think judiciously about how they encode outcomes - that is, how they symbolize and represent the outcomes they are trying to count. We provide a detailed case study of two students as they encoded outcomes in their work on several related counting problems within a computational setting. We highlight the role that a computational environment may have played in this encoding activity. We illustrate ways in which by-hand work and computer programming worked together to facilitate the students' successful encoding activity. This case demonstrates ways in which the activity of computation seemed to interact with byhand work to facilitate sophisticated encoding of outcomes.