The schools in my area do great on standardized tests. However, when my foreign exchange student started attending public schools in our town, we learned why--
that's all they do. They do test reviews for half the period and then watch movies like Happy Gilmore or Atlantis. He's watched over a dozen movies this year. And the subjects that aren't tested hardly teach anything (for instance, in American Government, he never even learned the 3 branches of government yet he got a 98 for the Semester
)
He now understands why we're going to homeschool, though it is strange to him since there's no homeschooling in China.