When you are adding larger numbers, it’s often better to use a written method. Column addition is a good written method to add one number to another. It involves putting the digits of each number into ...

Use Base-Ten diagrams and standard, expanded, and word forms to represent numbers. Warm up with a Mystery Math Mistake as you add two 2-digit numbers using a decomposition strategy. Find Which One ...

Cath Pearn is affiliated with both the Australian Council for Educational Research and the Melbourne Graduate School of Education, The University of Melbourne. I’m sure most people can remember trying ...