Elementary Students' Understanding of Variables in Computational Thinking-Integrated Instruction
Feiya Luo, Wei Yan, Ruohan Liu, Maya Israel · Proceedings of the 53rd ACM Technical Symposium on Computer Science Education · 2022
Variable is a common computer science (CS) concept and is being introduced to upper elementary students in computational thinking (CT)-integrated instruction. However, there is scant empirical evidence of when and how elementary students should learn variables. For example, national computer science (CS) standards advise introducing variables in grades 3-5 and a K-8 variable learning trajectory (LT) synthesized learning goals from the literature and hypothesized four levels of thinking in working with variables. Yet, little empirical research lies behind these. This mixed methods study examined elementary students' understanding of variables. Participants were sampled from two fourth-grade classes from a Midwestern elementary school that implemented a series of CT-integrated math lessons. Students' written responses to variables assessment items were analyzed. Additionally, cognitive think-aloud interviews were conducted with nine students to elicit students' understanding while solving the variables assessment items. Our findings suggested that most students lacked a conceptual understanding of using variables to create generalized problem solutions that could work with any set of inputs. Additionally, students had difficulty with specific mechanics of using variables such as storing user input in a variable, updating variable values, and using the values stored in variables. This study underscores the need for careful design, use, and analysis of elementary CT-integrated lessons and assessments to introduce and reinforce the conceptual understanding and specific mechanics of variables for elementary students.