Developing mathematical reasoning is achieved in this activity through If, Then task cards for Cuisenaire® Rods. Cuisenaire® Rods have the unique ability to take students into the abstract. This activity proposes changing the value of the rod and the measuring rod, and it has students explore the implications of those changes. Students ponder and use the information they know to reason how changing the value of the rod would affect the value of the other rods. "If white equals ten, then red equals what?"
Students should be familiar with counting by tens and hundreds. This activity is found after the literal work of Gattegno's Textbook 1 and within the number work. Students usually generalize that white equals one, red equals two whites, green equals three whites and so on. This generalization is challenged in this exercise.
There are 3 lesson plans. The first two are specific while the latter is not. The first lesson introduces the challenge of changing the rod value. The second lesson introduces the challenge of changing the measuring rod. The third lesson is general in nature. At this point, it is suggested that the activity should be incorporated in the monthly math routine to continue practicing and extending mathematical reasoning.
There are 10 If, Then Charts with 4 corresponding task cards for a total of 40 task cards. Task cards are 2 sided providing problems on the back to be solved based on the new values of the rod. If, Then Charts can be used to help students to solve these problems.