Find the Starting Amount Word Problems
Help your student work backward from an ending total to an unknown starting amount.
Teaching notes for parents and teachers
How to teach it
Build the final collection first. Remove the objects that arrived later and connect what remains to the unknown starting amount.
Example to work through together
Use the model below as you explain the example. Have your student point to the quantities as you discuss them.
Before: an unknown number of books.
Change: 4 books arrive.
After: 13 books.
? + 4 = 13
13 − 4 = 9
There were 9 books on the shelf before Ella arrived.
Ask your student
Are the new objects already included in the final total?
If your student needs help
If the student adds again, show how that would count the arriving objects twice.
Make a practice set
Select the worksheet, answer key, or both. When both are selected, the answer key prints after the questions. Keep it separate if you want your student to work independently.
After your student finishes
Choose one story and read it forward using the child’s answer as the starting amount. Does adding the new amount produce the final total? If it does, the quantities fit. If not, return to the before/change/after sketch.
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Grade 1 selected skill connection: 1.OA.A.1 (selected story structures). See the Common Core standards for this grade. This worksheet does not cover every requirement in the standard.