Qualitative Approach to Graphs of Functions in a Microworld

Abstract

This paper deals with a teaching experiment of how

6th grade students understand the rate of change with

covariational reasoaing 1n a LOGO-based microworld

JavaMAL We introduce the function graphs using the

traces of a turtle swimming in the JavaMAL microworld in

which textual commands are used not only for controlling

the turtle's motion but also for modifications and

reflections on students' thinking. We found that visual and

symbolic representations for the rate of change can work

together for a meaningful qualitative approach to the

graphs of functions.