Chapter 1: The Sweet Science of Ice Cream

In July 2017, amidst a significant heat wave and as the Larsen C iceberg commenced its journey into the ocean, a unique gathering took place in Manhattan. High school educators came together for an ice cream “support session,” exploring how the combination of ice, salt, cream, and sugar could be harnessed to teach various mathematical and scientific principles. This workshop was part of “Summer Think,” a three-day conference hosted by the non-profit Math for America, which annually supports 100 master teachers and invests heavily in educational fellowships throughout New York City.

The agenda for Summer Think included various sessions, such as a comprehensive exploration of “Climate Justice” and a workshop titled “Winning Hearts and Minds,” which resulted in a guide for teachers based on student feedback. One student poignantly described high school as “a place where teens are deprived of half of their lives.” In light of this, ice cream has emerged as a delightful remedy; in fact, America produced over 918,643 million gallons of ice cream last year alone, reflecting a 5 percent increase since 2014.

Chemistry instructors Rachel Jun from Columbia Secondary School and Laryssa Kramarchuk from Frank McCourt High School spearheaded the ice cream workshop. They drew from Kramarchuk's elective course, “What’s Cooking?”, which involves determining the heat of chili peppers and examining fermentation in root beer. Kramarchuk emphasized the importance of a non-linear teaching approach, where students design their own experiments based on their interests, which can help alleviate anxiety surrounding math and science. “I had to let go of the need to know everything,” she noted, encouraging a collaborative exploration with her students.

For the ice cream experiment, teachers utilized a straightforward recipe to serve as a scientific control:

In a large Ziploc bag, mix:

• 2 cups of ice
• 1 cup of salt

In a smaller Ziploc bag, combine:

• ½ cup of milk
• ½ cup of heavy cream
• ¼ cup of sugar
• ¼ teaspoon of vanilla extract

Seal the smaller bag and place it inside the larger one. While shaking it to the beat of OutKast’s “Shake it,” the teachers engaged with the learning process. “Frustration means you’re learning,” Kramarchuk reminded them.

Two essential concepts explored during this experiment are “solubility” and “freezing point depression.” The transition from liquid to solid states allows for a sensory experience of creaminess. As Harold McGee discusses in his seminal work, On Food and Cooking, the addition of sugar modifies the freezing process, preventing ice crystals from forming too rigidly. This principle dates back to the 13th century, where it was discovered that adding salts to ice allows for colder temperatures that facilitate the freezing of sugared cream.

"It’s a non-linear approach to teaching," Kramarchuk reiterated.

As the teachers shook their bags, they paused to record the temperature of the slush every minute. The experiment demonstrated that varying amounts of sugar affect the freezing point, leading to different results based on the ingredients used. The process of ice cream making can be summed up by the mnemonic “BARF”: Break bonds, Absorb energy, Release energy, and Form bonds.

This experiment primarily emphasizes stoichiometry, the mathematics behind chemical reactions, but it also opens the door for calculus discussions related to the melting rates of ice cream. According to Math for America teacher Andrew Wille, understanding the relationship between the radius of melting ice cream and its volume can explain why immediate licking of a cone is essential to prevent excessive dripping.

Additionally, there are opportunities for more abstract inquiries, such as a paper on conic optimization in ice cream constraints or experimental philosopher Jonathon Keats's "anthropocenic sorbet," which encodes climate data into flavors for deeper understanding.

In the classroom, as time dwindled during the ice cream-making process, Kramarchuk ensured there was ample time for sharing results. By the time the Beatles played, the ice cream had solidified, yielding a deliciously creamy and flavorful product. As Kramarchuk passed around chocolate syrup and sprinkles, the teachers reflected on the fun and educational value of the experiment.

Siobhan Roberts is the author of Genius at Play: The Curious Mind of John Horton Conway. Her essay "An 'Infinitely Rich' Mathematician Turns 100" featured in The Best Writing on Mathematics 2017.

Chapter 2: Fun Science Videos to Enhance Learning

The first video demonstrates a fun and cool science experiment involving ice cream that can be replicated at home, showcasing the chemistry behind the delicious treat.

The second video provides a sugar glass recipe, further illustrating how science can be integrated into enjoyable culinary projects.