Jacob has started a new unit in math - unknown addends. A sample problem would look like this: Jacob and Allison have 435 jelly beans between them. Jacob has 181 jelly beans. How many does Allison have?
If you are in second grade, this is supposed to process as: 181 + ____ = 435. Then you add up: start at 181; plus 9 = 190; plus 10 more = 200; plus 235 more = 435. Therefore the answer = 9 + 10 + 235 = 254.
If you are normal, you process this problem as 435 - 181 = 254 (making whatever 'borrowing from the neighbor digit' you need to).
Jacob is apparently quite normal - as I tried to follow the worksheet they sent home on unknown addends; he quite insistantly told me that it was not an "add" MOM, it was a "subtract." Ok - fair enough - let's do it that way.
What was funny was that Brian was also looking at the Unknown Addends How To For Parents sheet this morning and had almost the exact same reaction. "This is not an addition problem - it's a subtraction problem!"
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