DescriptionIn the sixth clip Erik and Alan worked on the task: Which is larger, one half or three fourths. Erik showed, using the orange and red train as one, that the difference between the two fractions was...
DescriptionIn the second of five clips from this classroom session, Alan worked alone at his desk on a new task that the researcher, Amy Martino, had posed. He built models to find the difference between one...
DescriptionIn the second clip, Kimberly and Audra worked together on the task: Which is larger one half or three fourths. Kimberly built a model using an orange and red train, two dark green rods, and four light...
DescriptionIn the third clip, researcher Amy Martino then worked with Mark and Laura. Mark justified his solution using each model he built. The researcher asked Mark if he thought that a different model might...
DescriptionIn the fifth clip Michael and Brian extended their model using the orange and red train to show thirds and twelfths in addition to fourths. They showed that the difference between two thirds and three...
DescriptionIn the first clip a visitor worked with Danielle and Gregory on the second task of comparing two third and one half. Danielle showed her using the twelve-centimeter long model, that three fourths was...
DescriptionIn the fourth of five clips from this classroom session, the researcher, Amy Martino, returned to Alan and questioned him about the third model that he had built for finding the difference between one...
DescriptionThis video was recorded during the first of many research sessions in a yearlong study conducted in a fourth grade classroom by researcher Carolyn Maher and colleagues. At the start of this session,...
DescriptionIn clip seven, researcher Carolyn Maher told the students to use the remaining class time to challenge their partners with problems using the rods. Erik asked Alan, “If a light green was one third,...
DescriptionIn the fifth of eight clips from this session, researcher Carolyn Maher asked the class to give a number name for the red rod if the brown rod was called one. Danielle explained that it would be...