Description
TitleBuilding large models to show equivalence, a generalization, Clip 2 of 3: Brian's conjecture
PublisherNew Brunswick, NJ: Robert B. Davis Institute for Learning, , c1993-10-11
DescriptionIn the second clip, researcher Carolyn Maher asked the students what the model that was next in size would look like. Brian said that it would equal the length of twenty-four white rods. The researcher asked what the white rod would be called in that model. Michael conjectured that it would be one twelfth, but did not explain why he thought so. Meanwhile Brian concluded that it would be one twenty-fourth. Alan and Erik said that they had built that model, and proceeded to build it on the overhead using a train of two oranges and a purple rod as one. The researcher asked the students what the white rod would be called in Erik and Alan’s model. The students answered that it would be called one twenty-fourth. She also asked them how that model can be used to solve the original problem that had been posed. Erik and Alan showed directly that the difference between two thirds and three quarters in this model was equal in length to a red rod or two white rods, and that the solution to the problem was one twelfth or two twenty-fourths. Amy then suggested, that purple rods could be placed on the model to show one sixth. Andrew, Erik, and Alan challenged Amy, asking her why the purples would be necessary on this model. Erik asked her why they would be necessary, since the solution was one twelfths and the purple would be too big. The researcher suggested that perhaps Amy was answering a different question, and saying that there were other ways to make trains. The researcher then said that she could ask the students to compare one sixth or three quarters, and Erik and Alan conceded that it would then be necessary to show sixths in the model.
Student ParticipantsAlan (student), Andrew (student), Beth (student), Brian F. (Colts Neck, student), David (student), Erik (student), Jacquelyn (student), James (student), Michael (Colts Neck, student)
RightsThe video is protected by copyright. It is available for reviewing and use within the Video Mosaic Collaborative (VMC) portal. Please contact the Robert B. Davis Institute for Learning (RBDIL) for further information about the use of this video.
Date Captured1993-10-11
Local IdentifierA94A95A96-FRC-CMPRF-CLIP002
Related Publication
Type: Related publication
Label: Ed.D. dissertation references the video footage that includes Building large models to show equivalence, a generalization, Clip 2 of 3: Brian's conjecture
Date: 2009
Author: Yankelewitz, Dina (Rutgers, the State University of New Jersey)
Name: The development of mathematical reasoning in elementary school students' exploration of fraction ideas
Reference: http://hdl.rutgers.edu/1782.1/rucore10001500001.ETD.000054787
Related Publication
Type: Related publication
Label: Ed.D. dissertation references the video footage that includes Building large models to show equivalence, a generalization, Clip 2 of 3: Brian's conjecture
Date: 2008
Author: Reynolds, Suzanne Loveridge (Rutgers, the State University of New Jersey)
Name: A study of fourth-grade students' explorations into comparing fractions
Reference: QA.R465 2005
Source
Title: A94, Building large models to show equivalence, a generalization (classroom view), Grade 4, October 11, 1993, raw footage.
Identifier: A94-19931011-CNCR-CV-CLASS-GR4-FRC-CMPRF-RAW
Source
Title: A95, Building large models to show equivalence, a generalization (presentation view), Grade 4, October 11, 1993, raw footage.
Identifier: A95-19931011-CNCR-PV-CLASS-GR4-FRC-CMPRF-RAW
Source
Title: A96, Building large models to show equivalence, a generalization (side view), Grade 4, October 11, 1993, raw footage.
Identifier: A96-19931011-CNCR-SIV-CLASS-GR4-FRC-CMPRF-RAW