During this session, Carolyn Maher asked the students to find the number of one third meter long bows from three, nine, twenty-seven, and eighty-one meters of ribbon. The students worked in partners or groups to solve this set of tasks. Several students used ribbon strips and rulers, and some of these students took their work out to the hallway so that they could measure a true-to-scale model of the task. Others used pencil and paper calculations, and were asked by Carolyn Maher to justify

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... usage of the standard multiplication algorithm, and to record their justification. Many of these students discussed why they knew to multiply the length of the ribbon by three in order to find the number of ribbon lengths one third of a meter long that were contained in the ribbon length. After some time, the class came together to discuss what they had found, and the students were asked to write about their solutions.