Semantic Reasoning in Young Programmers

Reading, tracing, and explaining the behavior of code are strongly correlated with the ability to write code effectively. To investigate program understanding in young children, we introduced two groups of third graders to Microsoft's Kodu Game Lab; the second group was also given four semantic "Laws of Kodu" to better scaffold their reasoning and discourage some common misconceptions. Explicitly teaching semantics proved helpful with one type of misconception but not with others. During each session, students were asked to predict the behavior of short Kodu programs. We found different styles of student reasoning (analytical and analogical) that may correspond to distinct neo-Piagetian stages of development as described by Teague and Lister (2014). Kodu reasoning problems appear to be a promising tool for assessing computational thinking in young programmers.