Sweet Percentages

This week is tax week in the USA, never a week that gets people very excited. It does get me thinking about percentages though. That brought to mind a fun activity I did with my middle schoolers one year that served as an assessment after we’d been working on percentages for several weeks, M&M Percents.

The assessment consisted of only four questions:

1. “What percentage of your M&Ms is each color?” I provided them with a chart and filled in the colors for them. The students did their work on the back of the paper and wrote the final percentages on the other half of the table. Each student’s answer for this question was slightly different, but because there is actually a formula for how many of each color goes into each bag (which is what question three is based off of), the answers were quite similar. I also highly advised all of the students to make a chart of their own with the total number of M&Ms of each color in it. This had two advantages: I had raw data to work from when checking answers, and they could eat their candy sooner rather than later (I only pointed out one of the advantages to the students.)

2. “Today is the 16th day of the month and Miss Bowman’s favorite color is green. I want 16 green M&Ms. If 4% of each package consists of green M&Ms, how many M&Ms need to be in the package for me to get exactly 16 green M&Ms?” Besides assessing their percentage skills, this question also allowed me to assess their abilities with writing an algebraic equation from a word problem (a skill we’d learned in a previous unit). The first time I gave this assessment was on the 16th of whatever month, and I honestly don’t remember if I updated this question the next time I used it, but it wouldn’t be hard to do.

3. “The Mars Candy Company has published the average percentage of M&Ms in a bag by color. If a regular sized bag of M&Ms has 48 pieces of candy in it, how many can you expect of each color?” I tried to find the official publication of these numbers again, but was unsuccessful. I did learn that the percentage actually varies based on which factory the M&Ms were packaged in (there are two), at least according to Stats Medic. I provided students a table for this question as well (they once again had to show their work on the back) and used the following percentages:

  • Red- 13%
  • Blue- 24%
  • Green- 16%
  • Yellow- 14%
  • Orange- 20%
  • Brown- 13%

4. “Write your own percent problem based on your bag of M&Ms.” We are always trying to push students to think deeper and use higher order thinking, to go up a level or two on Bloom’s Taxonomy, and that’s what this question was aiming for. I also wanted them to practice their math writing skills in preparation for the state testing that was coming in the near future. I gave a lot of grace on this one and, provided the question was related to percentages and made mathematical sense, gave full credit for whatever they came up with.

I would love to tell you that the students didn’t complain at all, and passing out chocolate candy with my assessment resulted in happy students; but anyone who’s ever taught middle school, or even met a middle schooler, would know instantly I was telling a lie. Of course my students whined–they were taking an assessment. Was there less whining than usual? Yes…after I promised an extra bag of M&Ms to anyone who achieved a score that was higher than their personal average. Yes, it’s true, I am not above bribery–especially when faced with whining middle schoolers and having to teach math first thing in the morning. What I can tell you with complete honesty is that this was a successful assessment and I liked how it was short, easy to prepare, hit multiple levels of Bloom’s, and allowed me to check students’ understanding of multiple standards. So, while I can’t promise you a fun or painless tax season, at least I’ve given you a possible assessment for your next unit on percentages. Happy teaching, everyone!