Math lesson comes alive with 100x100 In-N-Out burger surprise

The third graders in Christine Nguyen's math class at Jack L. Weaver Elementary school were hungry for a challenge. Fortunately, Nguyen had the perfect lesson to satisfy their appetites and probably give them food for thought for a lifetime.

“I want students to see the real-world connections and importance of math in our everyday lives,” Nguyen, who has a master’s degree in math education, said in a recent phone interview. She’s spent twelve of her sixteen years teaching at Weaver located in Rossmoor in the Los Alamitos Unified School District. Her goal is to make math “fun, engaging, and relatable to all students.”

Perhaps her most mouth-watering math lessons are the ones she’s been teaching for years that are focused on  In-N-Out burgers. Earlier this month, Nguyen told her students about the iconic fast-food chain’s so-called  secret menu which features burgers of different sizes, including a 3x3 consisting of three meat patties and three slices of cheese on a bun. The kids were excited to learn this secret menu would be the basis of their math lesson.

“Who doesn’t love food? In-N-Out and its secret menu is a definite attention grabber. Students’ eyes were wide open when I mentioned that we were going to do an In-N-Out investigation,” Nguyen wrote in a message to Spotlight Schools.

Third graders at Weaver are broken into different groups for math instruction. Nguyen’s class of around thirty students includes kids who have already mastered their grade-level concepts so she has some flexibility in what she teaches them.

Their delicious assignment was to figure out the cost and calories of different sized burgers including a 3x3, 20x20, and even a 100x100. They were given some of the information from the regular In-N-Out menu to figure it out.

“The challenge was to come up with two expressions or equations, one that would allow anyone to find the cost of any sized burger and one that would allow anyone to calculate the calories for any sized burger, the nxn,” Nguyen explained. To sweeten the challenge, Nguyen offered students a king-sized candy bar as a reward for finding the answers.

An animated class got to work. “If you could have been there and seen their excitement and felt the buzz in the classroom … they did not want to stop,” Nguyen said, sharing that the students were working together and encouraging one another. “It was so rich. They were all talking about different observations, different patterns.”

When math class was due to end, the students made the unexpected request to not be told the answers. “They didn't want me to give them any clues. They wanted to discover it on their own,” Nguyen said, explaining that some kids wanted to figure out the cost for a 1000x1000 and even a million by a million burger.

“I think this is the heart of teaching … igniting that light and drive for students to not learn because we want them to, but for them to have their own desire, you know, to want to learn, to want to do more and to feel like they could achieve anything they set their mind to,” Nguyen said.

Fueled by the students’ love for the lesson, Nguyen stretched the In-N-Out investigation into three sessions. But she had an idea to add something new. With the past two years of Covid-19 restrictions and rules on her mind, she thought it would be extra special to actually get a 100x100 into the classroom.

“You know what, I want them to be able to see it because how memorable and how cool would that be?,” Nguyen recalled thinking at the time.

She reached out to In-N-Out corporate offices with little success in getting the giant burger donated. Then she asked for some help. Christine Coxhill, a longtime parent volunteer at Weaver with experience asking for corporate donations for the school, said she would go to the In-N-Out located at The Shops at Rossmoor.

Coxhill’s son, Elliott, is in Nguyen’s math class and was really enjoying the burger-centered challenge. “He was just so excited and engaged and he just was so motivated to try and solve it because it was something that he was not used to,” Coxhill said of her son.

She was on board to bring the lesson to life for Elliott and his classmates. “I said you know what, I'm just gonna go in there and I'm just gonna beg. It’s not going to be pretty. I'm gonna beg for it,” Coxhill said in a phone interview half-joking.

Ultimately, after the In-N-Out manager made a few calls to corporate headquarters, he agreed to sell Coxhill 98 patties with 98 slices of cheese (a double-double of two patties, two slices of cheese and a bun was given for free, along with hats and stickers). But Coxhill and her other parent volunteers had to assemble the giant burger. Coxhill along with fellow parents Jenny Kwak and Susan Hsieh were up to the task, utilizing skewers to connect the patties and gooey cheese between two hamburger buns.

Coxhill admitted it was a little tricky piecing it all together. They put it into four boxes that they taped together and then placed that onto a wooden board on top of a cart to wheel into the classroom. She estimated the burger was more than three feet long.

“We are just so lucky to have amazing parent volunteers who are as passionate and as caring for our students' learning and their experiences,” Nguyen said of the parents who helped pay for the burger and put it together.

The big reveal

On the final day of the lesson, the kids eagerly anticipated learning the answers to their equations. How much does a 100x100 cost? I won’t reveal the answers here in case readers want to try the challenge at home.

In the final part of the lesson, Nguyen used an old In-N-Out receipt to reveal the answer and also showed a picture of a 100x100 burger. As students checked their work, there was a knock on the classroom door. A student answered and Coxhill and the other parents rolled in the real-life 100x100 burger accompanied with In-N-Out fries. The classroom was instantly filled with the fast-food chain’s signature aroma.

The kids couldn’t believe it. “They were standing up, their eyes were wide open, their jaws were dropped to the floor … they were so excited,” Nguyen recalled.

After examining the enormous burger the students got to eat some of it. Nguyen made a point to wrap up the lesson by reinforcing the point of it all – “Everywhere you look, math is present in some way, shape or form,” she said.

Nguyen’s students left class that day feeling nourished in more ways than one.