Using GeoGebra software the teacher can geometrically and fruitfully teach the concepts and algorithms of arithmetic operations in the elementary school. Our paper focuses on two important operations: ...

4. “Addition and Subtraction within 20” by Mathantics Mathantics offers a series of educational math videos, and this particular video focuses on addition and subtraction within 20. It explains the ...

Students put all their addition and subtraction skills together to solve equations.

The Logarithmic Number System (LNS) makes multiplication, division and powering easy, but subtraction is expensive. Cotransformation converts the difficult operation of logarithmic subtraction into ...

Add and subtract 1-digit and 2-digit numbers to 20, including zero. Solve one-step problems that involve addition and subtraction, using concrete and pictorial representations, and missing number ...