Test Scores and Science Mobiles

School districts will tell you it’s wrong to make decisions based on test scores — unless you conclude that textbooks are useless:

The district usually replaces the science textbooks every six years. This year, it would have cost the district $610,000 to buy new ones.

But district officials found they were wasting money on the books. When they looked at standardized test scores in science, they found that classrooms with the highest scores never touched the textbooks.

Districts don’t systematically use test scores to evaluate teachers, which makes the textbook evidence suspect. A correlation between textbook-free classrooms and higher scores doesn’t necessarily mean that textbooks lower scores. It might be that better teachers choose hands-on projects, but those teachers would improve achievement no matter which curriculum they used. If the textbooks used previously were inadequate, it could be that better textbooks would boost scores even more than exploratory activities. It’s also possible that the hands-on work is superior to textbooks, but that teachers who didn’t adopt the approach voluntarily won’t use it well when the district mandates it for all classrooms.

This should not be taken as a criticism of the mobile science lab described in the article, which sounds like a worthwhile addition to the curriculum. I just object to the arbitrary use of test scores to advance certain popular programs, like hands-on science, but not controversial policies like merit pay.