DescriptionIn the fourth clip from this session, Jessica reported that Jackie and Kelly’s argument was different than their original argument in which they had showed the difference between one half and one third to be a red rod, which they named one third. Jackie repeated their argument, using a model of a dark green rod, two light green rods, and three red rods. In her explanation, Jackie showed that one half was bigger by one third by one white rod. Jessica argued that they had used a different size candy bar, which was not allowed. Jackie then restated the argument, concluding that one half was larger than one third by the white rod, which was called one. After researcher Carolyn Maher questioned Jackie about the number name for the white rod, Erik volunteered to interpret their model. He said that he thought they meant to call the dark green one whole and that the whites would be called one sixth. Jackie and Kelly agreed that that is what they meant to say, and, upon questioning by the researcher, stated that they believed the difference was one sixth. The researcher asked them why it couldn’t be called one, and they responded that it was because the dark green rod was called one. Erik offered that if the dark green rod was called six, the light green rod would be called three, but agreed that it could not be done in this problem.
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Related Publication Type: Related publication Label: Ed.D. dissertation references the video footage that includes Comparing fractions, a whole class debate, Clip 4 of 5: An argument based on a different model 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 Comparing fractions, a whole class debate, Clip 4 of 5: An argument based on a different model Date: 2001 Author: Steencken, Elena Perrone (Rutgers, the State University of New Jersey)