An instrumental genesis perspective on the students' using spreadsheet for the interest concept and calculations

Spreadsheets are used in mathematics education because the software has the potential to organize data as well as to examine the relationship between variables. Studies on the concept of interest show that students have difficulties in interpreting the effects of variables in interest formulas. This study aims to examine students' use of spreadsheets in terms of instrumental genesis in tasks that deal with the mathematical structure of the concept of interest. The research was carried out with eight students of the course of finance mathematics at a state university. Data obtained through screen recordings, clinical interviews, and observation notes were analyzed through content analysis. The results of the study show that the students could see the relationship between simple and compound interest through the sequential operations in spreadsheets, they can interpret the changes in values by estimating through multiple manipulations, and they understand the necessity of entering cell addresses.