A73, Revisiting construction of large models to compare fractions (classroom view), Grade 4, October 8, 1993, raw footage

Amy Martino began the session by asking the students to discuss the task that they had worked on during the previous two sessions: Which is larger, two thirds or three fourths, and by how much? Several students offered conjectures of how to generate multiple models with Cuisenaire rods that could accommodate both thirds and fourths. Then, the students worked to reconstruct the models that they had found for this task in the previous session. One pair of students (Andrew and Jessica) successfully reconstructed and recorded their forty-eight cm long model, and another group, consisting of Meredith, Erik, and David, made an attempt to do so as well, but spent much of the session unsuccessfully trying to recall the exact length and makeup of the rod that had been assigned the number name one. At the same time, several other pairs of students worked on the task: Compare one half with two fifths. Which is larger, and by how much? Alan worked alone on this task, and described a method of generating multiple models to represent the solution to this problem.Transcript is also available.Robert B. Davis Institute for Learning. (1993).Building large models to show equivalence: A reconstruction. [video]. Retrieved from http://hdl.rutgers.edu/1782.1/rucore00000001201.Video.00006512