Non-teacher David Boies is absolutely convinced that we are plagued by old, bad, burned-out teachers; that's why we need to get rid of tenure, see, and replace them with young, inexperienced, poorly-trained teachers, like the ones at TFA, the vast majority of whom will leave teaching after three years. Makes complete sense...

Non-teacher Jonathan Alter is also gravely concerned that all of these bad, doddering senior teachers are taking jobs from awesome younger teachers when layoffs come (no word from Alter on what he thinks about those layoffs themselves, especially in light of the news that we've gone backwards in how much we spend in per pupil on education).

Non-teacher David Bernstein is sure that the problem must be those rotten pensions teachers get. In his construction, pensions provide incentives for washed-up old farts to stay in the classroom, even when they clearly hate their jobs.

(It's worth noting that Bernstein claims it takes 30 years to "get a pension," but the majority of systems vest at five years, and all vest under ten. Yes, you get less when you have fewer service credits, but you still get a pension. Let's try to get this stuff right, please.)

Bernstein's argument is a traditional piece of pension-bashing logic, premised on the notion that there are large numbers of old, exhausted teachers who would love to ditch their jobs, but only stay because of artificial pressures and protections.

Now, I know that actual evidence never stopped Boies or Alter or anyone from the reformy side of things from making an argument. However, at the risk of offending their moral outrage against senior teachers and their unions, I'll just ask:

Is there any evidence that America is awash in poorly-performing senior teachers?

Let's answer that question by first looking at the composition of the teaching corps. This chart is from staffing data I've used before from the NJ Department of Education, compared with data from the National Center for Education Statistics.

NJ tracks fairly well with national numbers, so we'll be able to look my home state in more depth in a minute and get a more refined view that likely reflects the nation as a whole. But let's take a moment to see what we've got with these national numbers.

Around 40 percent of teachers have 15 or more years of total experience; a solid majority of teachers have less than 15 years of experience. On this basis alone, we ought to question the notion that scads of burned-out senior teachers are a critical policy concern: if we take 15 years to be the cut point, it turns out most working teachers aren't even that senior to begin with.

Granted, 40 percent is still a good number -- but 15 years is hardly a lifetime of working. So how do teachers break down in experience when we look at it with finer precision?

Less than 8 percent of the teaching force has 30 years or more of experience. I ask again: even if we assume there are high rates of burn-out -- an assumption for which we have little to no evidence -- why would we think ineffective senior teachers were such a serious problem? There just aren't enough senior teachers in the profession to justify all the concern about their relative effectiveness.

If anything, we ought to be concerned that 20 percent of the teaching corps has been repeatedly demonstrated to be less-effective than their more experienced colleagues:

No one debates this:teachers gain most in effectiveness in their first few years of teaching. Of course, we need new teachers, and if they can only improve through actual experience, that's a price that must be paid. But I'd think reformers would be far more concerned with doing whatever it takes to make sure younger teachers are better prepared to lead their own classrooms, rather than focusing on the small number of senior teachers who may or may not be ineffective.

This is a matter of priorities: we can worry about the 15 to 20 percent of inexperienced teachers we know are less effective, or we can concentrate on the less than 10 percent of senior teachers we think might be less effective.

Which brings me to the next part of this: what evidence is there that teachers lose their effectiveness late in their careers? And do we have any evidence that pensions or other incentives cause burned-out teachers to stay in the profession past their due date?

More in a bit...

A critical education policy issue?