We conducted a classroom teaching experiment (Cobb, 2000) during the last three weeks
of Mathematics for High School Teaching, a capstone course for prospective secondary school
teachers. There were thirteen students enrolled in the course, ten of whom agreed to participate
in pre-and-post interviews. Data was also collected in the form of in-class videorecordings, inclass
assessments, homework assignments and student responses to two items placed on the final
exam. The design of our instructional sequence was based in part on our interpretation of the
aforementioned readings.