Cinco de Mayo Math, by Paula J. Maida

A celebration of Cinco de Mayo can spark a math fiesta!

Integrating mathematics across the curriculum offers students the opportunity to link ideas in a natural, impactive way. I shared these interactive math activities with fourth graders on Cinco de Mayo, a holiday honoring Mexican independence. These fun activities allowed for connections to be made between mathematics and other content areas such as history, and also within the area of mathematics.

Geometry and probability.
To kick off the "Fiesta of Math," I designed a worksheet for students to explore the connections between geometry and probability. The flag of Mexico offers rich math questions since it is not simply one third of each color, due to the emblem on the white region. Therefore, students need to think in terms of geometry and measurement to reason through questions including, "If the flag were lying underneath the piñata, and a piece of candy randomly fell on the flag, what is the probability it would fall on white?"

Into the sombrero.
Next, I placed 11 wooden cacti into a sombrero. Each cactus had a letter on it and together they spelled "Cinco de Mayo." The students were able to witness the connections between fractions and probability by linking the question, "What fraction of the letters are 'c'?" with "What is the probability that if you randomly select a cactus, you pick a 'c'?" "Are you more likely to pick a 'c' or a letter other than 'c'?" "What letter(s) are most likely to be picked?" Picking without replacement was explored, resulting in students recognizing how this concept changed the denominator and sometimes the numerator.

The importance of zero and one was then explored: "If Lindsay reaches in to pick an item, what is the probability she will pick a frog?" (0/6 or 0) "A cactus?" (6/6 or 1). The students were challenged to obtain a fraction less than zero or greater than one. Their inability to do so spurred discussion about the limits of answers for probability questions.

Pull-string piñata.
The students were particularly excited to see the pull-string piñata in their math classroom. While traditional piñatas are broken open with a stick, piñatas are available today that have strings attached to the bottom. Only one of the many strings will pull open the trapdoor to release the candy. This type of piñata offers a simple application in conditional probability as students recognize that their chance to pull the correct string depends on the outcome of students before them.

The plan was to have each child answer a math question before pulling a string. As the first student stepped forward I asked, "What is the probability you choose the magic string that drops the candy?" The answer is 1/30. His classmates quickly reasoned that he was more likely to not choose the magic string. Of course, I also anticipated that he would walk away with an unmagic string dangling in his hand. Yet, as Aerrol tugged on his randomly chosen string, the unlikely event happened! The trap door opened and the students were ecstatic. The irony of the moment was that I had numerous math questions planned as the suspense was to build so, when the trapdoor fell early, I momentarily thought I had lost some teachable moments. Luckily, it was quite the contrary. The students' wide-opened mouths of shock resulted in an even more powerful math lesson as they witnessed firsthand that while an event may not appear very likely to happen, anything is possible.

Choosing math over candy.
Only a handful of candy had spilled out so far and we all agreed that it would be fun to "talk more math" and dive for candy later. I tucked the trapdoor closed and we continued, with students stepping forward to answer questions before removing a string. "If you closed your eyes and randomly selected one of the colored strings, what is the probability of choosing red?" (6/29).

The piñata was decorated with tissue paper curls of various colors so I asked the next child, "If you closed your eyes and randomly picked a tissue paper curl, what is the probability that it is yellow?"

"One out of 13," the student answered.

"How did you estimate that?"

"I counted 13 rows of colors and one of them was yellow," he replied.

Technically, the rows of color did not all contain the same amount of tissue paper curls (for example, the body contained more surface area than the ears), but the student designed a meaningful strategy to obtain a rough estimate and he was commended for his reasoning. To place further emphasis on the importance of zero, I asked, "Knowing Aerrol is holding the magic string, what is the probability that your string choice will open the trapdoor?" "0/27, so it won't happen," a student answered.

I continued with various questions and the culminating piñata question of the day was, "What percent of the students in this classroom would like to have the piñata's candy spill all over the floor now?" One of my students exclaimed, "100%!" and the trapdoor was then swiftly re-opened.

Paula Maida (above) invites a student up to give the pull-string piñata a good yank.

The end of the fiesta.
After the excitement settled, each student created two unique probability questions about his or her particular bag of piñata candy and then momentarily switched questions and candy bag with a partner. The students solved these problems as our fun math fiesta drew to el fin. These engaging activities truly captured students' interest in probability while building understanding and use of terminology through experiments related to our celebration of Cinco de Mayo.

For a Fiesta of Math on Cinco de Mayo worksheet click here.

Paula J. Maida teaches prospective teachers at Western Connecticut State University in Danbury, CT.