The purpose of this project is to help students in traditionally-rigorous intermediate algebra courses appreciate the power, beauty and utility of their own knowledge of quadratic equations.
Parabolas exist everywhere. For ages, people longed to define these shapes more precisely than words could describe. Math is the language that made this possible. Precisely defined by quadratic equations, parabolas found in nature could now be recreated in the built world—in architecture, in bridges, in sculpture. Consequently, this exciting discovery has been passed down through the ages as part of the standard algebra curriculum.
For today’s students, however, quadratic equations are but a sterile artifact of that once-exciting quest for a language that could describe natural form and prescribe its construction. For them, quadratic equations are just another thing they have to learn in algebra class. The connection between quadratic equations and the real world has been lost and, for many students, so has any intrinsic motivation to learn to build and calculate them.
A constructivist approach to learning holds that we care about learning those things that hold meaning for us, and nothing is truly meaningful until we have experienced and discovered it for ourselves (Karagiorgi and Symeou, 2005; March 2003). Discovery and insight involve making connections with what we already know (Piaget 1969), and is enriched through interaction with others. According to David Jonassen (2003), a constructivist approach involves designing educational experiences that support meaningful learning by clearly defining the problem and activity space, by providing opportunities to construct knowledge, compare divergent perspectives, and use real-world problems or tools, and by encouraging collaboration, conversation, group consensus building, complex intellectual engagement, mindful thinking, and reflection. This teaching guide specifically targets each of these components.
In the lessons that follow, students engage in semi-structured experiences designed to support accurate and meaningful knowledge construction. Students are asked to locate photographs of parabolas in art and architecture, and then are encouraged to work collaboratively to develop and confirm accurate equations describing the forms using the language and structure of mathematics. Problem space is defined by the instructor/facilitator by guiding student energies toward location of parabolas (as opposed to other conic forms). Students spend several days engaged in experimenting with, creating, refining, and confirming accurate equations through group collaboration, conversation, consensus building, peer assistance, and peer review. Throughout this collaborative process, students consider divergent opinions and perspectives, ultimately settling on the solution that they believe best describes the initial selection of architectural art. Creating and verifying original equations certainly qualifies as an intellectually-challenging task in line with the constructivist philosophy of complex intellectual engagement. At all stages of the project, students use real-world tools of their own choosing—CAD software, drawings and sketches of graphs, and 2D or 3D graphing calculators---to validate the equations they have created. At the conclusion of the project, students and instructors individually and collectively engage in mindful reflection about the value of what they have experienced and learned.
In Constructivism: Theory, Perspectives, and Practice, Catherine Twomey Fosnot (2005) reflects upon lessons learned from attempts at constructivist reforms in mathematics education. Fosnot describes several examples of mathematics teachers who use a technique of asking neutral questions (“Can you tell me why that is?”) to allow students to enter an unsteady state of disequilibrium as they attempt to solve real-world, “messy” mathematical problems. Fosnot coins the term mathematizing to describe learners’ processes for creatively finding solutions in real-world contexts. She reminds us that professional mathematics is never a process of transmitting facts and knowledge from teacher to student—the essence of the work of mathematicians is to define a problem, notice patterns, develop hypotheses, and experiment with equations (the language of mathematics) to accurately describe a real-world phenomenon or suggest a mathematical theoretical solution.
Pilot results
The lessons described in this Guide were originally developed for intermediate-algebra high school students and then refined and piloted with intermediate algebra students at a community college. By allowing our students several days to “mathematize,” we were able to capture the struggle, frustration, and heady success of creating original mathematic work. They wanted to experiment; they were so engaged and excited that they lingered after class; one student was inspired to learn AutoCad just for fun.
Following the Piagetian model of intellectual development, the following lesson plans are divided into two types: high school and college. Although the spirit of discovery and inquiry learning is still present in both sets of lesson plans, college age students are asked to engage in different and slightly more sophisticated type of reflection activities than high school age students. In addition, the lesson plans for the high school unit are divided into three lesson plans rather than the four lesson plans for the college age students. This difference reflects more the practical differences between high schools and colleges (high schools frequently ban the use of cell phones during school hours).