#### "The Big Race" Lesson Study

The goal of my group 's lesson study was to see if students could make sense of their answers. The focus of our lesson study was story problems in systems of equations. My peers and I noticed that our students would solve a math problem, get an answer, and not check to see if their answers make sense in the context of the problem. Say one of the variables was the number of people. Our students would get a negative number or a decimal. They wouldn't think about what they were solving for and instead proceed to the next problem.

In this groupworthy task, we had students solve a system of equations. We had the students work together to write the equations for each of their racers (which was another thing they struggled with). They then had to find the point of intersection for all of the racers. Finally, they had to analyze their answers in the context of the problem.

We did this task twice in two Algebra 2 classes at two different high schools. Below is the task we gave our students to complete. Next to that are my reflections after each implementation.

First Implementation Reflection

Second Implementation Reflection