DescriptionAfter a discussion in the previous clip in this series about how many towers can be built three cubes high when selecting from two colors, researcher Alice Alston asks the students to create towers three high to see how many there are, reminding the students that all the towers must be different. In this clip, Jeff and Brian create towers three cubes high from the set of towers they had created four cubes high in the Towers series. They remove the bottom cube from each tower and then remove the duplicate towers which they notice. They try to reconfigure the duplicates to make them unique, but each time realize that they already have the new tower in their existing set. As they continue trying to create additional towers, they find that the new towers are duplicates of ones that they already have and that in fact some of them match more than one existing tower, so they remove additional duplicates. As they continue to work at finding new towers, Jeff declares that he is “not convinced”. The researcher asks the pair what they think and they realize that they have more sets of “matches”, which they remove. They work some more at finding new towers, until Brian declares, “We’re convinced” and Jeff tells the researcher that there are “definitely” fewer towers. Jeff counts the towers and finds that they have seven towers. The researcher points out that one tower is missing its opposite, so Jeff tries to build a tower to be its opposite but is unsuccessful at first. The researcher shows Jeff an example of opposite towers, and Jeff makes a few more attempts at creating the opposite tower until he is successful. The researcher and Jeff then arrange the eight towers in pairs of each tower with its opposite.
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 Group Sharing, Clip 4 of 6: Jeff and Brian work on finding towers three cubes high 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: B51, Towers Group Sharing (presentation view), Grade 3, October 11, 1990, raw footage. Identifier: B51-19901011-KNWH-PV-CLASS-GR3-CMB-T4T-RAW