Identifying and Correcting Early Misconceptions in Learning Python: Variables and Assignment Operator

Contribution: The purpose of this study is to identify students' early misconceptions in the use of variables in a firstyear computer programming course using Python. Background: Misconceptions start early, persist during the semester and prevent many students to make adequate progress to learn more advanced programming concepts. Research questions: Which are the most common misconceptions in the use of variables and the assignment operator in a first-year computer programming course using Python? What learning objectives and activities can guide instruction and scaffold students' progress to prevent or correct those early misconceptions? Methodology: We assessed student performance (n=108) in four different conceptual categories: problem understanding, variable assignment, data types, and arithmetic expressions. Assessments were implemented as multiple choice and short answer questions that involved reading and/or writing small flowcharts or snippets of Python code. Findings: We have identified prevalent students' misconceptions in problem understanding, variables and assignment operator syntax and semantics, data types, and arithmetic expressions in a first-year programming course using Python. To guide instruction and scaffold students' progress to prevent or correct those early misconceptions, we propose a set of activities organized around specific learning objectives aimed at correcting those misconceptions early on.