As parents, we are understandably concerned about class size: The number of small — and growing! — bodies crammed into classrooms is something that’s easy to see and understand. And logic tells us that the teacher’s attention is a finite thing; we, naturally, want our own children to get as much of that precious resource as possible.

But Dr. William Ouchi says there’s another number we should pay attention to, one that few schools calculate and publish: the total student load, or TSL. Rather than the number of students in a classroom at any given time, it is the total number of students each faculty member teaches. A math teacher with six classes of 30, for example, has a total student load of 180, if none of those students overlap. But if that same teacher were teaching three combined math/science classes of 30 students each, the total student load would be cut in half.

When Ouchi, a business professor and cofounder of the UCLA School Management Program, wrote his first book, Making Schools Work, recommending that school systems decentralize and hand hiring and budgeting power over to principals, the education world snapped to attention. His second, The Secret of TSL, looks closely at eight decentralized school systems and how they have — or have not — reduced total student load.

One of those systems is the St. Paul Public Schools, which, under superintendent Pat Harvey in the early part of this decade, experimented with a form of decentralization. (Since Harvey’s departure the system has returned to a more traditional form of administration.) During her tenure, Ouchi writes, SPPS did not reduce total student load but it did track and publish numbers for each teacher — unlike almost any other system he has observed.

In his book, he also describes at length how Phalen Lake Elementary in St. Paul approached literacy. By teaching literacy at different times for each class — and sending the other classes to the library or media center, they were able to pull in several teaches at once and break each class into small groups of six, essentially giving kids one-on-one attention in this crucial area.

Ouchi says the optimal student load is around 80. He has completed a peer-reviewed study showing that reducing TSL meaningfully improves student performance.

Minnesota Parent talked to him about why this is.

Were you surprised when you saw how closely TSL was tied to student performance?
We were really surprised, because we put all the traditional measures of teacher performance into our analysis and the only one that had an effect on student performance was TSL.

Why is it so important?
The reason that’s so crucial is that frequently a student runs into a wall and they aren’t going to raise their hand in class and ask an embarrassing question, but if their teacher has a time that they know they can go one on one, it may just take 15 minutes for them to get that little bit of direction and a lot of encouragement so they can keep going.

If you have 200 students or in LA Unified, you have 250, that’s not going to happen, there’s never going to be a time when that student feels like they can talk to the teacher one on one. But if you have 75 or 80 students it’s going to happen on a regular basis.

Beyond 80 students, teachers can’t develop a bond with the students. And without that bond, students won’t permit the teacher to push them when they need to be held to account.

Class size is a very powerful idea. It’s something many teachers and educators are concerned about. Are we worried about the wrong thing or are we worried about part of the right thing?
It’s part of the right thing. At Phalen Lake, if you calculate the administrator ratio — the percentage of all the employees in administrative nonteaching positions — it was about 10 percent. I looked at some comparable traditionally managed elementary schools in Chicago and they were at an administrative ratio of about 32 percent.

I saw this often enough and I saw it in different forms. And this light bulb went off: What’s happening in the successful school is that they’re getting down to one-on-one instruction for at least a few minutes every day for every student.

They do this by shifting money and positions?
They do it by dropping administrative positions by saying to the teachers, “We’re going to offer you a trade. We’re going to drop your class size in literacy but in exchange we’re going to have fewer people to perform administrative tasks for you. For the teachers that’s such a positive trade that they’re virtually always happy to do it.

If it’s all about staffing ratios, why can’t a traditionally managed system change that as effectively as a decentralized one?
It would be helpful if districts actually measured the administrative ratio in each school and reported it. That would create some pressure. But what would not work is to do it by central office fiat. As I write in the book, every one of those schools has found a unique way to do this. Teachers are not widgets. One teacher wants to teach three courses in physics, but would also like to teach a course in ecology and another in philosophy. Well, that teacher is not replaceable with any old physics teacher and is going to open up possibilities that are unique to that school.

I listen to central office people all the time. This is the way they’ve been trained to think: “It’s my job to figure out what schools need and see that they get it.” But they can’t go to 50 schools — or 700 — and do that for every school. That’s why you need decentralization.

Is it really possible for cash-strapped schools to do this?
I was surprised at how quickly it is possible for a school to reduce TSL and how far they can reduce it if they try. When the schools I saw in New York City got serious about reducing TSL, they got down to the 50s and 60s. Now, New York City has more money than most schools, so maybe other schools can get down to 100 if you try.

Most of the elite private schools have TSLs in the range of 60–65 students. Most public middle and high schools are in the range of 120–250. In a sense, TSL is the main difference between private and public schools.
In a typical private school, everybody teaches. The headmaster teaches. The director of admissions teaches. It’s not unusual that the budget director teaches. Everybody teaches. That’s the only way they can afford to get to these low TSLs. Public schools have abandoned that idea that teaching is what we do and everybody teaches.

Why is it that we’re not talking about this?
That’s why it’s called the Secret of TSL! Absolutely nobody is talking about this! If you call up five principals and ask them, “What’s your TSL?” I guarantee you’ll go 0 for 5.

Tricia Cornell edits Minnesota Parent.

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