Concepts
of whole number operations refer to an understanding of how and why operations
work the way they do. Students work with models of operations that demonstrate
why algorithms were developed. The models generally require that students
use concrete materials or manipulatives in their demonstrations.
The concepts of operations are based on students' intuitions about how to solve problems from real contexts. That is, if two children were picking mangoes, to find how many they had altogether, they would put the two sets (or collections) of mangoes together and count them. This is a model of addition known as "joining."
In grades K4, the mathematics curriculum should include concepts of addition, subtraction, multiplication, and division of whole numbers so that students can