Lynbrook South Middle School seventh graders enrolled in Justin Randazzo’s Math 7 Accelerated class participated in an interactive math activity on Feb. 14 about the time it takes caffeine to metabolize in the body. The class had just completed their unit on linear equations and system of equations but Mr. Randazzo wanted to show students that not every relationship on a graph happens in a straight line. Developed by Oceanside High School math teacher Rocio Saborido for algebra 1 and 2 students, Mr. Randazzo modified the math activity for his seventh grade class.
At the beginning of the activity, the class discussed energy drinks such a Red Bull and Monster Energy. They spoke about some of the ingredients that are found in these beverages such as sugar and caffeine. The class specifically looked at the amount of caffeine in one Red Bull or one cup of coffee. Before jumping into their experiment, the students made predictions on how long it would take to completely eliminate caffeine from their blood stream.
While working in small groups, the students received two cups of clean water which they combined into a beaker. The beaker with clean water represented a person’s blood stream before caffeine. Mr. Randazzo, along with math teacher Michelle Bains, contaminated each group’s “blood stream” with green food dye to represent caffeine. The food dye amounted to 80 milligrams of caffeine which students learned can be found in a can of Red Bull or one cup of coffee. The class was then challenged to think about how they could eliminate half of the caffeine in their blood stream after drinking one of these beverages.
They poured half of the colored water from their beaker into a cup and then dumped it into a waste bin on the table to demonstrate caffeine leaving the blood stream. To gain half of their blood stream back, the students poured clean water back into their beaker to serve as clean, non-caffeinated blood. Each group continued the process and documented their attempts until their beaker/blood stream was clear without any food dye/caffeine left. Some groups had to conduct more trials than others to get their blood stream caffeine-free.
Throughout the experiment, the students completed a chart of the time, the trial number and how many milligrams of caffeine were in the body. While starting with 80 mg, the amount of caffeine decreased over time but did not result in a straight line on their graphs. After the experiment, the class shared their results and examined whether or not caffeine ever fully leaves the body, according to their math. The activity was a great way to get students engaged, learn about how caffeine affects the body and most importantly, learn that not all data results in a perfectly straight line.