Curated OER
Developing Strategies for Addition and Subtraction
Primary graders develop strategies to assist them with addition and subtraction. They discover number combinations and numerical facts which enable them to add and subtract more effectively. Students use these techniques to complete...
Other
Dan's Math: Basic Skills Topics
College professor Dan Bach offers a review of various basic topics in arithmetic, pre-algebra, and algebra. Order of operations, exponents, square roots, variables, and combining terms are just a few of the many topics covered.
Lawrence Hall of Science
The Math Page: Skill in Arithmetic: Elementary Addition
This resource offers six brief arithmetic lessons: sums less than ten, sums of ten, and sums between ten and twenty, doubling, zero, and a set of general practice problems.