DescriptionIn this clip, researcher Alice Alston asks Stephanie and Dana how many towers they have created. The two girls had been working on the Towers Problem introduced in the first clip in this series. After they reply that they have found seventeen towers, Alice points out that their group of towers contains a duplicate tower. Alice then questions the girls about how they can be sure that they have found all the towers, and Stephanie and Dana reply that they were “running out of blocks” so they checked their towers and eliminated the duplicates. Stephanie then decides to check for duplicates again to be certain that they are all unique. During her check, she comments that she found “cousin” towers which she explains as two towers that are the same when one is turned on its head. Alice then shows the girls two towers that she considers “cousins”, towers which have the same pattern but with opposite colors. Stephanie continues looking for duplicates. When she finishes, the girls record their solution with explanations of how they arrived at their answer.
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.
Related Publication Type: Related publication Label: Ed.D. dissertation references the video footage that includes Towers with Stephanie and Dana, Clip 3 of 5: Checking for duplicates and discovering “cousin” towers Date: 1992 Author: Martino, Amy Marie (Rutgers, the State University of New Jersey)
Name: Elementary students' construction of mathematical knowledge : analysis by profile Reference: QA.M386 1992
Source Title: B50, Towers with Stephanie and Dana (student view), Grade 3, October 11, 1990, raw footage. Identifier: B50-19901011-KNWH-SV-CLASS-GR3-CMB-T4T-RAW