Sweet Math: Dan Meyer’s Starburst Lesson and Probability

When I first discovered that Dan Meyer’s lessons could bring math to life in a new way last summer, I took the time to investigate the three-act math options he created. One that struck me as extremely engaging was his lesson on Starbursts. I saved it in a probability folder knowing full well that probability was slated for the end of our school year. A glimpse of it was so memorable; I actually had the wherewithal to incorporate it into my lesson plan this past week, in April. That might not seem earth shattering, but trust me, it is.

The first act of the lesson launches with the opening of Starburst two packs. The pack reveals one yellow and one pink. A skull and crossbones image appears over the yellow Starburst and an audible yuck is heard in the background.  A second pack is then opened, revealing two yellow Starbursts, which leads to two skull and crossbones over the Starbursts and an even louder yuck sound. Clearly, Meyer does not seem to like the yellow Starbursts. The camera then focuses on a large pile of Starbursts two packs.

That is the end of act one. Immediately, students began to debate the merit of each flavor of Starbursts and began to wonder aloud. I let them question and debate each other for a minute. Alerting them at this time I would not provide them with additional information, I asked them to make a prediction that was both too high and too low regarding how many yellow Starbursts they believed were in the pile. We wrote several too high and too low predictions on the board, and then I asked them if I could provide them with any information to help them solve the problem, what they would like to know.

Immediately students’ hands shot up and the first student I called on asked, “How many packages of Starbursts are there in that pile?” Another asked how many flavors there were. Several students scoffed at the second question and, somewhat exasperated commented, “FOUR!!! Have you never eaten Starbursts before?”  One asked to find out how many double flavor packs there were in the pile. The rest of the students loved that idea and complimented the thinking involved behind that one. And of course, inevitably, one student just wanted the answer. Sigh; there is always the need for that request!

The next two slides I shared were images from Dan’s lesson (Act 2) that revealed that there were 287 packages in the pile and the four flavors of (not by flavor, color) yellow, red, orange, and pink.

Now that students had a bit of information at their disposal, I asked them the following questions:  “In those two-packs, how many packages do you think have two yellow Starbursts? How many do you think have one yellow Starburst? What do you believe the overall percentage of yellow Starbursts is in the pile? Use what we have learned in our probability studies to make a prediction.

Students walked around the room and worked with anyone and everyone to try to figure out the answer. I was amazed as I witnessed the thinking displayed. Many students immediately wrote the total possible outcomes of Starbursts such as yellow-yellow, yellow-red, yellow-pink, yellow-orange, etc. They then used total possible combinations to convert to favored outcomes. With that, they used ratios and came up with their predictions. They found a way to apply the procedural math we had been studying for the previous two days in class on their own accord.

Students shared their predictions and many were close to each other, a few, not so close…Funny enough, many students who had different answers, upon hearing their peers’ strategies recognized probability mistakes that they made. When it was time to reveal Act 3, students were cheering. I love to hear cheering in my class, over, yes, MATH!!! They quickly calculated their percent error and found out how very close (and far) each was in their work.

A specific feature of Dan Meyer’s lessons is that he leaves them quite open for interpretation.  In my mind, he recognizes that teachers are not robots in the classroom and deserve the flexibility to interpret and customize to our heart’s content. This gave me an idea for an extension at the end of the lesson.

I pulled out a bag of Starbursts and had each student grab two. We recorded the flavors of the Starbursts pulled from the bag and made a frequency table displaying the sample space on the board. Unfortunately, we ran out of time, but I recorded our data on a frequency table so we could do a follow up the next day. My first question I plan to ask is:  What type of questions and answers can be generated with this information?

For those who might be wondering, students were granted permission to eat the two Starbursts they selected. After all, I wanted to make sure that this math lesson left everyone with sweet memories.