Why Co-Teaching Fails in Most Buildings, and What Actually Fixes It

Co-teaching does not fail on training. It fails on the master schedule. And you cannot fix a master schedule with a professional development day.

I have co-taught. I have co-taught well, with a partner I had for three years and a shared prep period, and I have co-taught badly, with a partner I met in August, in a class I was assigned to fourth, while carrying two other co-taught sections with two other people.

Same teacher. Same training. Completely different classrooms. The variable was not effort.

What the research actually says

Let me be honest about the evidence, because the sales version of co-teaching is not supported and I am not going to pretend otherwise.

Murawski and Swanson (2001), "A Meta-Analysis of Co-Teaching Research: Where Are the Data?", in Remedial and Special Education, reviewed 89 articles and found only six contained enough quantitative data to compute effect sizes. Outcomes varied widely.

So the honest read is that the evidence base for co-teaching's academic effect is thin. Anyone selling you co-teaching as a proven test-score intervention is going past what the research supports.

Which means implementation quality is the whole ballgame. Two teachers in a room is not a model. It is a staffing decision. What happens inside the room is the intervention, and that is where the qualitative work gets interesting.

Scruggs, Mastropieri, and McDuffie (2007), "Co-Teaching in Inclusive Classrooms: A Metasynthesis of Qualitative Research," in Exceptional Children, synthesized 32 qualitative studies. Teachers broadly supported co-teaching. But the dominant model in practice was one teach, one assist, in classrooms that stayed traditionally structured, even though that model is not well supported in the literature.

One teach, one assist. That is the special educator standing at the back of the room while the content teacher lectures. Every administrator reading this has walked past that room this year.

And here is the finding that should change what you do on Monday. Joint planning time was rare, and the needs teachers identified, which were planning time, training, and student skill level, were largely traced back to administrative support. Administrators often assumed that placing two teachers in a room was sufficient.

Why the special educator ends up at the back of the room

It is not a confidence problem, and it is not a content problem, although both get blamed.

It is a preparation problem, and it is structural.

If I do not know what tomorrow's lesson is until I walk into it, I cannot co-teach it. I can circulate. I can redirect. I can help the kid who raises his hand. That is one teach, one assist, and I did not choose it. The schedule chose it for me.

Give me the lesson three days out and a planning period with my partner, and I can tell you which two students will lose the thread at minute twelve, what the vocabulary trap is, and which of the four models we should use for this specific lesson. That is co-teaching. It takes about twenty minutes of shared planning a week, and the twenty minutes have to exist somewhere on the schedule.

At the secondary level it gets harder still. Dieker and Murawski (2003) note additional constraints specific to the secondary level, including block scheduling, high-stakes testing, and content-area demands. A high school co-teacher is being asked to co-plan in a content area they may not be certified in, against a pacing calendar they do not control, in a schedule that was built around graduation requirements.

None of that is fixed by a workshop on the six models.

The three questions to ask before you buy another day of PD

These are master-schedule questions. They cost nothing except the will to answer them honestly.

Do co-teaching partners share a common planning period? Not "can they find time." Is there a period, on the schedule, where both of them are free, and is it protected. If the answer is no for most of your pairs, that is your finding, and everything else on this list is downstream of it.

Are partnerships stable year over year? The first year of any co-teaching pair is spent learning how the other person teaches. If you reshuffle partners every August, every pair in the building is permanently in year one. You are paying for co-teaching and receiving one teach, one assist, forever.

How many partners is each special educator assigned to? This is the one that gets missed. A special educator with four co-taught sections across four different content teachers is co-planning with four people, learning four sets of content, and adapting to four teaching styles. Nobody does that well. Two partners is workable. Four is a fiction you are paying for.

Ask those three, and you will usually find the answer to why the model is not working, and it will not be about teacher buy-in.

What it costs to fix

Almost nothing, in dollars. That is the frustrating part and it is also the good news.

Build the master schedule with co-teaching pairs as a constraint rather than a leftover. Pair people first, then schedule around the pairs. Most buildings do it in the other order, which is why the common planning period is always the thing that does not fit.

Then protect the common prep. The fastest way to kill co-teaching in a building is to use the special educator's planning period for coverage. Every time you pull them to cover a class, you have made the choice that the shared planning does not matter, and your staff will read that choice accurately.

Cap the number of partners. Keep the pairs together for more than a year. And then, once those three things are true, spend money on the PD. It will actually take, because the people in the room will have somewhere to put it.

Do it in the other order and you get what most districts get. A trained staff that still runs one teach, one assist, because that is the only model the schedule permits.

What to do now

Before the next master schedule is built, pull three numbers.

How many co-teaching pairs share a protected common planning period. How many pairs are in their first year together. And how many distinct partners each special educator is assigned to.

You already have all three. They are in the schedule you built last spring.

Then walk the co-taught classrooms and look for where the special educator is standing. If they are at the back of the room, you do not have a teacher problem. You have a schedule problem wearing a teacher's face.

And know what it costs when you get it wrong. A special educator who spends the year as a classroom assistant in someone else's room is a special educator who is quietly deciding whether to keep doing this job, which is a much more expensive problem. They are also the person who has to write the IEPs and hit the timelines afterward, on a prep period you just spent. If you want to see what that week actually looks like, here is the job on the other side of the co-taught class.