Learning the concept of fractions is among the most challenging topics in school mathematics. One of the main sources of difficulties in learning fractions is related to "natural number bias" (Van Hoof, Verschaffel & Van Dooren, 2015). Applying properties of the natural numbers incorrectly in situations involving rational numbers can…

The acquisition of number conservation is a critical step in children's numerical and mathematical development. Classic developmental studies have established that children's number conservation is often biased by misleading intuitions. However, the precise nature of these conservation errors is not clear. A key question is whether conservation…

Tasks that ask students to label rational number points on a number line are common not only in curricula in the upper elementary school grades but also on state assessments. Such tasks target foundational rational number concepts: A fraction (or a decimal) is more than a shaded part of an area, a part of a pizza, or a representation using…

Speakers are known to make subject-verb agreement errors both when a number-mismatching noun intervenes between the head of the subject phrase and the verb (e.g., "*The key to the cabinets are on the table") and in configurations in which there is a number-mismatching noun that does not intervene (e.g., "*The cabinets that the key open are on the…

TORUS, a prototype technology-based educational diagnostic program, is described. The usefulness of TORUS to identify and remediate the mathematics misconceptions of students with learning disabilities is reported. Results suggest the need for greater emphasis on conceptual understanding in mathematics instruction. (Author/DB)