There’s been a lot of discussion on Twitter lately on the issue of class size:  how Bill Gates, Michael Bloomberg, and all sorts of other billionaire reformers and their foundations argue that the number of students in a classroom doesn’t matter nearly as much as the quality of the teacher.

I want to respond to that claim, generally.  I’m not going to link to any of the specific counter-arguments, or the original statements of these billionaire reformers or their organizations at this time.  Because their research is flawed.

That problem is scaling.

Every private school I know of touts class size, and the ratio of faculty to students, as a key part of its marketing program.  In exchange, they expect parents to part with sometimes-exorbitant sums of money… money to pay those faculty, to keep those ratios low.

The truth is, most of my colleagues in private school are not substantially smarter, nor better trained, nor more aware of the latest teaching methodologies, than our colleagues in public school.  True, more of them hold degrees in the subjects they teach — sometimes advanced degrees — but they often are less aware of teaching methodologies, or how to reach students with more complex issues.

Yet it’s easy for private schools to find people who are competent at handling and teaching twelve students or sixteen students at a time.  It’s not to say they’re bad because they’re not.  They know their subjects, and they have a sense of how to deliver their content, and for the most part they love their subjects.

Ask those same people to teach twenty-five students, though, and the number of them who prove competent at that task probably drops.  We all know people who are great at handling ten people, who are not good in crowds.  Some of them are a little less enamored with the work of grading all those papers.  Others are less enthusiastic about teaching grammar to a class where there are three trouble-makers who sit together and trouble her daily, rather than one ‘trouble-maker’ who can usually be persuaded into participating most days.

Increase the number of students to thirty or forty… or sixty, as some of the current proposals suggest — and the number of effective teachers drops again.

Of course, there are going to people who dispute my suggestion that scalability has anything to do with this.  So I can only offer an alternate ranking of jobs by their skill at managing people:

  1. squad leader
  2. lieutenant
  3. Captain
  4. Colonel
  5. Major
  6. General

We don’t expect military officers to manage large numbers of people right out of school, and do it well.  We have a defined career path for them, and we create opportunities for them to grow and improve through training and development. When a lieutenant demonstrates that they’re not capable of being promoted, they’re honorably discharged.

What the various ‘reformers’ propose is that we throw our young squad leaders and officers into the colonel’s job, when they haven’t yet developed the necessary skills to manage a squad or a platoon.  And we often don’t provide them with enough experienced grunts to do their job effectively, as the army usually provides sergeants and other veterans to wet-behind-the-ears lieutenants fresh from OCS.

Meanwhile, in my job at a private school, I’m teaching roughly the same number of students that I did at the start of my career.  The private schools have done a great job of maintaining the same level of service — the same teacher to student ratio — for fifteen years, largely by raising prices on a regular basis, which public schools can’t do.