This very interesting article in the Washington Post by a public school teacher in Northern Virginia makes the point that the degree of difficulty of the Virginia Standards of Learning tests is, if anything, too low, and that passing the SOLs is nothing for the kids or the school systems to brag about.
These conclusions seem credible as statements against interest, in the language of the rules of evidence. Teachers and school administrators (and newspapers who want to make trouble or side with the teachers' unions) have some incentive to complain that the SOL tests are too tough.
I've heard a similar discussion in connection with the degree to which law school students should be prepared for the bar exam during law school, which prompted one fellow to say that if they learn what's on the bar exam, at least they will have learned something. The same can be said of students who pass the SOLs - at least they learned something.