Perhaps you have seen the Facebook post by an angry mother who is upset about her daughter’s Common Core-based math problem. There’s a larger lesson here, but it’s not about the Common Core.
Click here for the Facebook post by Larisa Yaghoobov Settembro
The problem asked was,
Carole read 28 pages of a book on Monday and 103 pages on Tuesday. Is 75 pages a reasonable answer for how many more pages Carole read on Tuesday than Monday?
And the student responded,
Yes, 75 is a reasonable answer because 103-28 = 75
for which she was deducted a point for not estimating the answer of 70, since that appears to be the lesson about what is a “reasonable” answer. The teacher marked:
-1 [pt] Estimate 100-30 = 70
For background on Common Core math methodologies, see Key Shifts in Mathematics
Right math lesson, wrong question
Other blog and news sites have taken this on, for and against the question. I think this is a horrible question, but not because the exercise of rounding is worthless. It’s a poor assessment question because, Continue reading