The relation to operands (RO) principles describe the relation between operands and answers in arithmetic problems (e.g., the sum is always larger than its positive addends). Despite being a fundamental property of arithmetic, its empirical relation with arithmetic/algebraic problem solving has seldom been investigated. The current longitudinal…

Observed gesture and speech to investigate patterns of change in third and fourth graders' strategies for solving mathematical equivalence problems before and after an intervention. Children who received instruction were more likely to generate new strategies. Gradual change was more common. Abrupt strategy change was more common in children who…