AP Test Scores... The Shoemaker's Children?

May 12, 2011

In an ExxonMobil TV ad supporting the National Math and Science Initiative (NMSI), the voice-over says that “high schools. . . enrolled in the NMSI have raised AP test scores by 138%.” ExxonMobil reasserts this claim on their corporate website.

This claim struck me as a little strange. High school Advanced Placement (AP) tests are scored on 1-5 scale, and a score of at least 3 is typically needed before college will allow credit for a high-school course. Scores of 5 are rare — roughly comparable to scoring 750 or better on an SAT test. So even if the average “before” AP test score was only a 2 – which seems low, since only students already enrolled in high school AP classes take the AP tests – that would mean that the “after” average would have to be 4.76 (i.e., an increase of 2.76, which is 138% of 2). For an entire group to average 4.76 on a test where 5 is the hightest possible score, the overwhelming majority of them would have had to score a perfect 5!

So I went to the NMSI’s own website, where it discusses its Advanced Placement Training and Incentive Program (APTIP). It turns out the NMSI is reporting that high schools participating in APTIP saw a 138% increase in students receiving a “qualifying” score (i.e., 3 or higher) on math and science AP tests. That is truly significant progress. But stating that there was a 138% increase in students scoring 3 or better, is not the same as claiming that “scores improved” by 138%.

I’ll repeat that the NMSI deserves congratulations for this accomplishment. However, I would suggest that an accomplishment is diluted when people describe it in language that’s inaccurate and that overstates when overstating isn’t necessary. That this has occurred in reporting math and science test scores is ironic indeed.

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