MemberMay 25, 2020 at 1:48 pm
The word “difference” is so important. When I began teaching I did not have a good understanding of subtraction with a number line and the idea of compensation was confusing. Using the model with the unknown part I think is helpful to the students.
One area I wonder about is negative numbers and modeling subtraction. I have a goal to learn more ways to represent those and gain confidence with my own understanding.