Christine Fairless Connects With Her Students

Twenty five seventh graders at Bernard-White School in Union City were designing research stations for Antarctic researchers last week. After designing floor plans on computers, students investigated which insulation level was the best buy for reducing building and heating costs at the south pole.

Major projects in MMAP/Pathways ask students to take on the role of a math-using professional and carry out a design project from beginning to end. Memos from their fictional employer—along with other paper materials and computer software— aid students in their work. Students learn mathematics as they use it in their design and analysis of their design. Then Side Trips focus on the same content from a more pure mathematics point of view.

Antarctica is a 5-week project in which students design and analyze a research station for scientists working and living in the frozen south. Memo 3 asks students to find the level of insulation (measured in R-value) that minimizes total building and 20-year heating costs for their research station. Students create tables, rules in word and symbols, and graphs to investigate the problem and support their choice. Students learn how to build a formula from variables that represents the total cost. They use functions in which the variables are linearly and inversely related. The move from stating patterns such as “as R value goes up, heating costs go down” to more precise expressions such as T=B+20(12)H where T is total cost, B is building cost and H is monthly heating cost. They interpret the graph of this function to make their choice of the best R value for their design in the Antarctic climate.

The Side Trip, Direct and Inverse Variation, introduces students to the families of functions for the two relationships they uncovered in the R value problem. They explore the mathematical properties of these two families through examination of many examples.

So, within these lessons, students are learning significant mathematics aligned with the NCTM PSSM 2000, specifically with understanding functions through use of tables, graphs and verbal and symbolic rules. They identify graphs as linear or non-linear and contrast their properties. They learn about uses of variables, dependent and independent, and as parts of an equation. They solve a problem from a architectural and engineering context and draw inferences from the mathematical model and the real-life context to solve the problem.