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Afterschool Lesson Plan Database

Lesson Plan

Data and Probability: Marshmallow Madness
Subject: Math
Grade span: 6 to 8
Duration: 30 to 45 minutes
This lesson was excerpted from the Afterschool Training Toolkit under the promising practice: Math Centers


This sample lesson is one example of how you can implement Math Centers. In this activity, students collect data using large and small marshmallows, much like flipping a coin, to determine the chances of a marshmallow landing on its end or side.


Adapted from the Connected Mathematics Program. Lappan, G., Fey, J.T., Fitzgerald, W.M., Friel, S.N., and Phillips, E.D. (2002). How Likely Is It? Glenview, IL: Prentice Hall.

Learning Goals:



What to Do:

Teaching Tips:

Understanding Data

Each time students flip a marshmallow and record the result, they are gathering data, information that will help them determine the likelihood of that result happening again.

Interpreting Data and Writing Fractions

Once students have flipped marshmallows and recorded their answers, they are ready to write their answers as fractions and be able to say what percent of the time a given marshmallow will land on its side or end.

For example, one of the follow-up questions asks:

What fraction of the time will a small marshmallow land on its side, according to your experiment?

Sample Answer: If the marshmallow lands on its side 20 times, the answer is 20 out of 50 times. To write that as a fraction, you simply write 20/50. This can also be expressed as 2/5 (two fifths) of the time or 40%. It may be helpful to review converting fractions into decimals with the students, and to explore what the % symbol means and how it relates to decimal and fraction notation.

Evaluate (Outcomes to look for):

Click this link to see additional learning goals, grade-level benchmarks, and standards covered in this lesson.

Online Training for Afterschool Staff
The Afterschool Training Toolkit is available online free of charge.

The following resources can be used with the online Afterschool Training Toolkit to give you the resources you need to build fun, innovative, and academically enriching afterschool activities.