Today we had our annual Yr 13 M&M’s graph competition. Having just completed Perfect and Imperfect Competition with my Year 13 class I used a couple of packets of M&M’s to drum home the concept of marginal analysis MC=MR. It has always been something that students have struggled with but I am hoping this experience of creating graphs with M&M’s might help their understanding and when to use the concept. There is a three way process for learning about this theory:

- Students complete worksheets / multiple-choice questions that test their knowledge of the curves that make up the graphs.
- Students draw the graphs on A3 size whiteboards
- Students construct graphs using M&M’s

Profit is maximised at the rate of output where the positive difference between total revenues and total costs is the greatest. Using marginal analysis, the firm will produce at a rate of output where marginal revenue equals marginal cost. Below are a few of the graphs done today using M&M’s. The winner this year is Year 13 student Luke Davis – his graphs are the first and second below.

Student worksheet

Student graph on A3 whiteboard

Student graphs using M&M’s