DescriptionIn clip seven, researcher Carolyn Maher told the students to use the remaining class time to challenge their partners with problems using the rods. Erik asked Alan, “If a light green was one third, what would be a whole?” Alan responded that the blue rod would be called one. Alan asked Erik to find the rod that would be called one if the white rod was called one fifth. Erik said that the yellow rod would be called one. Researcher Amy Martino asked Erik to justify his solution. Erik began by showing that five white rods equaled a yellow rod in length. He then showed how he also found the solution by using the staircase model he had built on his desk and counting up to the yellow rod, which he called five. He also said, “And I know that that’s half of [the orange rod], and I know that yellow is half of orange, which is ten.”
Researcher Martino asked Alan and Erik, “If I call this [purple rod] two, what would one look like? Which rod would one be?” Erik replied that the red rod would be called one, and, when asked to justify his solution, explained that the red rod was half as long as the purple rod, and “half of two is one.” He then showed that two red rods equaled the purple rod in length. Erik asked Alan to find the rod that would be called six if the white rod was called three. Alan responded but there is no evidence that he justified his solution. Alan asked Erik to find the rod that would be called one if the purple rod was called one half. Erik named the brown rod one.
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Related Publication Type: Related publication Label: Ed.D. dissertation references the video footage that includes Fraction as number, an introduction, Clip 7 of 8: Erik and Alan pose problems as partners Date: 2009 Author: Yankelewitz, Dina (Rutgers, the State University of New Jersey)
Related Publication Type: Related publication Label: Ed.D. dissertation references the video footage that includes Fraction as number, an introduction, Clip 7 of 8: Erik and Alan pose problems as partners Date: 2001 Author: Steencken, Elena Perrone (Rutgers, the State University of New Jersey)