Texas public school students usually score pretty well in the federal government's NAEP school achievement tests, at least when adjusted for ethnicity. I've always wondered how they do it. It would seem like the kind of thing worth checking into.
One way, it turns out, is by excluding more students from having to take the NAEP than other states do. Texas excuses 10% of its 4th graders versus 4% nationwide and only 3% in California. (See p. 5 of this new report on the NAEP performance of the 5 biggest states.) So, Texas has simply made a large fraction of Below Basic scorers vanish. That's a nice little running start for Texas.
If Texas has figured out how to fiddle with that parameter, I wonder what else they've figured out?