BeginToReason
Megan Fowler, Tim Schwab · 2018
Computer science (CS) students often evaluate the behavior of the code they write by running it on specific inputs, studying the outputs, and then inductively reasoning to a more general understanding of the code. This is a good starting point in the student's career, but successful graduates must be able to reason deductively about the code they create and encounter. They must be able to reason about the code on all inputs, without running the code. This paper describes an online system named "BeginToReason" that is designed to introduce symbolic reasoning, and the results of its use. One hundred and fourteen students were asked to use BeginToReason after receiving no prior instructions on formal reasoning. Several weeks later, a question on their final exam tested their ability to utilize formal reasoning. Across all question variations presented to the students, they completed an average of at least 80% correctly indicating that the online tool is a useful tool for teaching formal reasoning. Subsequent analysis of the results indicates that student responses may have been influenced by the phrasing of the questions as well as their use of concrete numerical examples to solve the problem.