Graphical Approach to Teaching Compound Interest in High School Math Classes

Report published in the Proceedings of the National Conference on "Education and Research in the Information Society", Plovdiv, May, 2015

The topic of compound interest has its place in high school mathematics curriculum to introduce the students to one important application of exponential function. It prepares them to understand the basics of the most widely spread financial instruments like deposits and loans. Modern open source Dynamic Geometry Systems (DGS) like GeoGebra allow high school mathematics teachers to apply a dynamic graphical approach to the concept of compound interest. The elements of inquiry based learning implemented in math classes help students become independent and critical thinkers, decision makers, and discoverers. Experiments and observations with DGS serve students as a source of formulating and verifying the financial Rule of 72, the Continuous compounding concept, and their own hypotheses as well. Experience gained from the inquiry based learning activities accustoms the students to using DGS for analysis of financial situations later in life.

Association for the Development of the Information Society, Institute of Mathematics and Informatics Bulgarian Academy of Sciences, Plovdiv University "Paisii Hilendarski"