I’ve always been fascinated by the way a particular education issue will pop up at the same time in unconnected places. It’s a different phenomenon from pack journalism, where news outlets are aware of other news outlets reporting on something, and then they report on it, too. These are independent stories on an underreported topic that suddenly appear all at the same time.

We’ve seen it happen with performance pay, school lunches and childhood obesity, and the shortage of minority teachers. The most recent media wave concerns paying teachers who don’t teach.

The first and most prominent story on the problem, of course, is connected to The New Teacher Project report that revealed New York City was spending $81 million to pay teachers who weren’t actually holding jobs. This caused a firestorm of debate in the city, rebuttals by the union, and Internet screaming by everyone. The controversy also revived discussion of New York City’s “rubber rooms,” which contain an entirely different set of teachers who don’t teach.

A similar issue arose in Birmingham, Alabama, where the school board discovered it was paying almost $96,000 a year in supplements to 63 employees without knowing why.

The Detroit Public Schools has its own twist. The district has a $45 million deficit, partly because a number of teachers whose jobs were declared “excess” or “surplus” due to falling enrollment were never let go. That was good news for them, but bad news for the district because it wasn’t receiving funds to pay them anymore. Other areas of the budget were raided to pay these teachers, until the house of cards started to collapse.

“The teaching staff should have gone down as we closed schools and lost students,” said school board president Carla Scott, explaining that layoffs didn’t keep pace with declining revenues. “For the first time in two years, we actually know what’s going on. We should have been in crisis mode for the last 10 years.”

There’s enough ammo for all sides. In Miami, United Teachers of Dade President Karen Aronowitz wants to solve district budget problems by putting teachers back in the classroom.

”It’s a dirty little secret that happens inside the schools,” she said. “Sometimes, teachers will be assigned as team teachers and won’t be in the classroom at all. Some teachers have additional planning granted to them, and then they become quasi-administrators.”

Aronowitz added, ”We have found, especially in elementary schools, that you may have three or four assistant principals. “That just doesn’t make sense.”

I think the fact that this problem is widespread is a sad commentary on a badly bureaucratized public school system. But I’m not going to get all polemical about it. If you want a polemic, here’s a polemic.