Here's the WSJ's Barbara Martinez with an article that captures but one element of the courageous reforms taking place under Bloomberg and Klein: making tenure for teachers and principals something to be earned, rather than awarded automatically:

New York City principals are getting tougher: They denied tenure or continued the probation of a record 11% of teachers in the school year just ended, according to Department of Education data released Thursday.

Five years ago, less than 1% of teachers found themselves in the same predicament. Principals this year also gave hundreds more teachers "unsatisfactory" ratings. The results come amid a push by schools chancellor Joel Klein for greater teacher accountability and a harder stance on tenure. In a letter to teachers in February, he said tenure had become "an expectation more than an honor." He had also called on principals for the first time to consider student test scores when making tenure decisions, and the latest results show that they did.

"Our principals are retaining top teachers and they are dismissing low-performing teachers," said John White, a deputy chancellor. "They are doing it as part of a culture shift of using evidence of student learning."

Principals themselves also faced greater scrutiny, with 28% of them having their tenure denied or extended, versus 15% the year before.

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