DescriptionIn this short clip, James explains to Robert B. Davis his solution to the problem: Which is larger, one fourth or one ninth, and by how much? After some questioning, he explains that the train (i.e.,...
DescriptionIn this 8 minutes whole class discussion about early algebra ideas (specifically with regards to integers), Researcher Robert B. Davis models adding positive and negative integers to a class of...
DescriptionIn clip 5, researcher Carolyn Maher then asked the students to compare one half and one quarter and determine the difference between the two. The students worked in their groups to build models that...
DescriptionIn the third clip Alan presented another model to show the difference between one half and one third. He built a model using one dark green rod, two light green rods, three red rods, and six white...
DescriptionIn clip 4, researcher Carolyn Maher asked the class to determine the number name for the white rod in the first model that had been built, in which the orange and red train was called one. James,...
DescriptionThis first of 18 clips focusing on Early Algebra Ideas Involving Two Variables occurred toward the end of the first of two consecutive 6th grade class sessions. Researcher, Robert B. Davis, builds on...
DescriptionIn the second of 18 clips focusing on Early Algebra Ideas Involving Two Variables, Researcher Robert Davis writes the equation printed below on the white board and asks the 6th grade students to think...
DescriptionIn the eighth of 18 clips from Early Algebra Ideas Involving Two Variables on the second of two consecutive classroom sessions with the class of 6th grade students, individual students and pairs of...
DescriptionIn the ninth of 18 clips from Early Algebra Ideas Involving Two Variables on the second of two consecutive classroom sessions with the class of 6th grade students, the students note that the Truth...
DescriptionIn the third of 18 clips focusing on Early Algebra Ideas Involving Two Variables, when Researcher Robert Davis asks the students to explain what they understand to be the mathematical task, Milin...