Solving Problems with The Percentage Bar

Frans van Galen (Freudenthal Institute, Utrecht University)
Dolly van Eerde (Freudenthal Institute, Utrecht University)

Journal on Mathematics Education (JME)
Vol 4, No 1 (2013)

At the end of primary school all children more of less know what a percentage is, but yet they often struggle with percentage problems. This article describes a study in which students of 13 and 14 years old were given a written test with percentage problems and a week later were interviewed about the way they solved some of these problems. In a teaching experiment the students were then taught the use of the percentage bar. Although the teaching experiment was very short - just one lesson  -  the results confirm that the percentage bar is a powerful model that deserves a central place in the teaching of percentages.