Education Technology

Exponential Decay

Activity Overview

Students run a simulation using M&M'S® whereby they eat each of the M&M'S with the M facing upward. Each time approximately half the remaining M&M'S get consumed. The result is exponential decay. A truly memorable and satisfying mathematics investigation!


The aim of this activity is to provide students with an intuitive understanding of exponential functions, exponential decay and asymptotic behaivour, all done through the context of munching on M&M'S; your students will love it!


  • Exponential
  • Ratio
  • Decay
  • Asymptote

About the Lesson

Load up a cup with M&M'S. Pour them on the table. Eat all the M&M'S with M facing upwards. How many are left? Repeat! What a delicious way to learn about exponential decay. In the interests of limiting calorific intake, students are also introduced to simulations which introduce the notion of different rates and asymptotes. A truly memorable activity for all students.