My wife is a tenured teacher. There is no complacency in her teaching. Her grade level is the only one in her school to achieve any passing scores (75% students passing or more) the last two years on state exams. Yet she is deeply concerned whether she and her coworkers will achieve similar results this year or any year. There is simply a great variance among incoming classes to swing the balance from one side to another. And this is not unique to any social strata. But a high performing school district has more leeway for slippage without falling short.

I know many excellent school districts in Ohio, all of which utilize tenure. Tenure is not automatically granted in the first place. It encourages dialog among teachers and the community. The un-tenured might be browbeaten into submission or fired by a principal (and lest we forget, a principal teacher was simply first among equals), a superintendant, or a board. No one has demonstrated to me that tenured teachers as a whole provide inferior results.