You will often hear about an exciting strategy to help students learn: they should teach one another.
Imagine a unit on — say — “siege warfare.” And, imagine that my student (let’s call him Lancelot) learns enough about siege warfare to teach his classmates about …
… its strategic and tactical requirements,
… the benefits and detriments of siege warfare,
… the changes in siege warfare over time,
Well, Lancelot has LEARNED A LOT about the topic.
Even better, if Lance learns enough to teach this material effectively, that extra level of mental lift will no doubt benefit his understanding.
It seems that “students teaching students” could result in deeper learning. What’s not to love?
What’s Not To Love
Long-time readers know that I struggle to accept uplifting advice. If a teaching suggestion sounds really heartwarming and feels really good, I worry that all that feel-good warmth has distracted me from the skepticism that is my job.
In this case, “students teaching students” SOUNDS so wonderful. For that reason, I feel compelled to ask some tough questions and offer some downbeat assertions.
We know that humans have limited cognitive resources. For instance, adults have alarmingly small working memory capacities — and most of our students have less than we do.
How should Lancelot use those limited resources of his?
I — as the teacher Merlin — could ask him to focus on learning the topic.
Or, I could ask him to divide those resources: use some working memory to understand the core ideas, and some working memory to think about effective explanations and exercises that will help his classmates learn.
Sadly, the more WM that goes to teaching others, the less that Lance has to understand the topic.
Or, if Lance uses all his WM for understanding sieges and none for teaching, then his teaching will be really ineffective.
After all: who knows better than teachers that good teaching requires LOTS of cognitive resources.
In other words: I worry that asking Lance to teach his peers will have several bad outcomes:
Either: Lance won’t understand the topic well;
Or: his classmates won’t learn very much;
I might not like that conclusion; it certainly isn’t heartwarming. But a basic understanding of working memory’s limitations makes it hard for me to reject this perspective.
When I ask Lance to teach the other knights at the round table, I’m asking him to do two distinct mental tasks:
First: he has to understand siege warfare (or covalent bonds, or exponent rules, or…)
Second: he has to repackage that understanding into specific explanations and tasks that help others understand. (After all, that’s what teaching is.)
Note, however, that if Lance doesn’t understand covalent bonds, he can’t possibly teach that concept to others effectively.
For that reason, I (teacher Merlin) need at least one additional step:
I need to ensure that Lance understands the chemistry REALLY WELL before I set him off on his teaching question.
Here’s the kicker: our students typically are novices in the topics we want them to learn. Because Lance is a novice on the topic of covalent bonds, he simply CAN’T KNOW whether or not he understands them well.
As a beginner, he doesn’t understand enough to know if he understands.
Unless I structure my unit plan with great foresight and lots of double-checking, it’s likely that I’ll ask someone who simply cannot know if he knows to teach his classmates.
Whether or not I have helped Lance learn, I almost certainly have fallen short on my responsibility to ensure that Lance’s classmates learn.
Because I’m the luckiest guy on the MBE planet, I spent this last week working with 50 teachers in an online workshop. We discussed working memory and long-term memory and attention and schema theory — and all their myriad classroom applications.
Honestly, they were one of the most thoughtful and engaging groups I’ve ever worked with.
When I explained my skepticism about “students teaching students,” two participants pushed back with thoughtful rejoinders.
One said (I’m summarizing, not quoting):
When parents ask me how they can help their children study, I say:
“have them teach you the topic we worked on in class. Even if you don’t know a lot about it, you’ll know enough to be able to spot the weaknesses in their explanations, and to ask follow up questions.
And, you’ll get to know more about their school lives!”
Another said (more summarizing):
I have my students teach each other as a kind of review.
That is: each of them uses marker to draw a particular diagram (say: the digestive system) on their desks.
Then, they rotate to the next desk, and annotate in a different color: they add, they ask questions, they suggest updates.
Then, they rotate again, and add in yet a different color.
So, when a student gets back to her original desk, she has learned SO MUCH from her peers. And, she has helped her peers by making her own annotations.
In other words: we have LOTS of reasons to ask students to teach others.
“Teaching” vs. teaching
These comments helped my clarify my thinking, because they force me to define “teaching” more precisely.
In the first place, I should say that I think both of these teachers’ strategies are EXCELLENT. In both cases, students are — basically — using retrieval practice to review material.
That is: both teachers have already taught the concepts to their students. When students explain ideas to their parents, or recreate and annotate diagrams on desks, they must re-activate their prior knowledge.
In this case, students don’t simply review concepts (“review” = less effective). They retrieve concepts (“retrieve” = more effective).
However, neither of these excellent strategies precisely fits my definition of teaching. When I think of teaching, I think of…
… explaining a concept or procedure to someone who doesn’t yet know or understand it,
… with the result that this person does know or understand it.
So, for instance, the strategy of “teaching parents” succeeds whether or not the parents understand. The goal isn’t to benefit the person being “taught” (the parent), but to benefit the person “teaching” (the student who’s doing the explaining).
Or, the strategy of “teaching the digestive system” probably succeeds because the teacher ALREADY taught the material. The students aren’t providing original instruction; they’re reviewing (and perhaps adding to) knowledge they got from the teacher.
In other words: I worry about “students teaching students” depending on the definition of “teach.”
Having students explain ideas to someone else sounds like a great idea — as long as I don’t need “someone else” to understand.
Having student review ideas with each other sounds like a great idea — especially if Merlin already explained those ideas in detail.
Teachers should certainly invite students to explain their thinking to other people.
We should ask them to review with one another.
But, except in unusual circumstances, Merlin should teach Lance — and all the other round-table knights — before asking him to explain or review.
A final note. I think graduate students should be able to learn concepts independently and explain them well enough for others to understand. That’s their professional goal.
Perhaps college students can do so…although (remembering my own overconfident college days) I worry that this strategy might not succeed.
In my view, K-12 students almost certainly can’t meet the 2-part definition of “teach” above — certainly not without LOTS of careful training and review.
A final, final note.
This blog post (atypically) cites no research. I’ll start looking at research on the topic of “students teaching students” and report back.
If you have suggestions of studies you like, please let me know!