There was big news on Advanced Placement last week. The College Board announced thatmore students than ever had taken AP examinations and that more students than ever had scored at the top level--about one test-taker in seven pulled off a 5.

Getting a 5 on an AP exam is a big deal--the tests are hard, and there's no doubt about it. For lots of people--perhaps fewer of them in education than in the general public--really hard is really good; there's nothing like a "rigorous" examination, requiring months of preparation and inspiring raw fear, to show that kids are learning something valuable. Jay Mathews' now practically industry-standard Challenge Index of school rankings is built just on the percentage of students at a school who sit the exams, regardless of their scores.

Click here to continue reading.