unannounced into a classroom and determine whether a teacher is performing. Teachers--be they secular or ecclesiastical--do not like unannounced classroom visits. A good teacher has no such fear.

One need not resort to test results--teachers simply teach to the tests--to determine competency. Observation is key. As Justice Potter Stewart famously observed in the obscenity case, Jacobellis v. Ohio, he couldn't define the word but "I know it when I see it." The same is true of good teaching.