Two-digit addition and subtraction is a difficult concept for children and may take a lot of work with hands-on material before getting to the number strategies (see videos below). At school, we do a lot of work with grouping objects into tens, adding and subtracting groups of tens and ones.
In the picture on the right, you can either ask your child how many coins there are in total (10+10+10+2) or you could ask your child to build 32 using the ten frames. Then ask: How many if there were 10 more? 10 less? 20 more? 20 less? Keep working with groups of objects to gain more mastery of what equations like 25 + 33 really LOOK like visually. |
Number Strategies for 2-digit addition and subtraction
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