In the popular TV show “Friends,” one episode features the character Rachel preparing an English trifle (a multi-layered dessert served in a large, footed glass bowl) for her roommates. A traditional trifle is typically made with layers of ladyfingers, custard, jam, fruit, and whipped cream. Much to the shock of Rachel’s friends, though, one of the layers in her trifle is a combination of sauteed beef, peas, and onions!
Middle School Science Teacher Sarah Bain was inspired to use the funny episode to illustrate to her eighth-grade Earth Science students how sedimentary rocks and fossils are formed. This semester, the budding geologists learned that common sedimentary rocks such as sandstone, limestone, and shale often start as sediments that are carried by rivers and deposited in lakes and oceans. When buried, the sediments dry out and form rock. Over time, the layers of rock build upon one another.
Rocking Out in the Kitchen
On a recent sunny morning, the students gathered in the Bryan Innovation Lab kitchen. Ms. Bain started class by playing an excerpt of the “Friends” episode (which elicited lots of laughs) and explained that the group would create their very own individual trifles (minus the beef mixture!) to represent the different layers of sedimentary rocks found in nature.
Using a variety of fun foodstuffs (vanilla wafers, jam, strawberries, chocolate pudding, rice cereal, green sprinkles, bananas, and whipped cream), students scooped the ingredients into mini trifle cups. Ms. Bain explained that to represent the strata of sedimentary rocks, the order of the layers was vital.
“The crushed vanilla wafers, which represent the oldest layer of sedimentary rocks (which can be billions of years old), go in first,” she said. “Then comes the jam, half of the pudding, the sliced strawberries, and another layer of vanilla wafers.” The next layer was especially important. “Mix the other half of the chocolate pudding with the crispy rice cereal and green sprinkles,” she instructed. “That’s your meat, peas, and onions-inspired layer!” Topping off the trifles were spoonfuls of sliced bananas and fluffy mounds of sweetened whipped cream.
Ellie Hirsch ’28, who hadn’t seen the “Friends” episode before the lesson, said, “My biggest takeaway from the trifle project was that sedimentary rocks form in layers. Plus, I enjoyed eating the final result!”
“This lesson was so exciting to plan,” shared Ms. Bain. “From coordinating with Director of Dining Services Anne Maury Haapala to executing the lesson, my students exceeded my expectations. Their smiles and engagement inspire me to find new ways to be creative in the classroom. The study of sedimentary rocks is fascinating in itself, and when it’s combined with a hands-on lesson such as this one, students make important (and sweet!) connections.”