Two-Digit Subtraction with Regrouping
For students who have a difficult time remembering when to borrow we use our extremely effective trick of - "if the bottom number is bigger you borrow from your baby" - with the baby being the number in the next column to the left. Sure, it sounds funny, but the "b" "b" "b" repetition is easy to remember since students find this humorous. The key here is that the student soon learns that when answering a subtraction problem - they must first determine if the bottom number is bigger - if it is bigger then regroup (borrow), if not, then just subtract.
|Answer the two digit subtraction problem.|