Get Students Talking to Each Other with ABC Discussion Stems

Renata Salas

[warmly] Welcome to the show. Colin, I had one of those very ordinary classroom moments today that somehow explains an entire problem. I asked a question in 3rd-period ELA, one kid answered, another kid raised her hand, and I could SEE it coming -- she was not about to respond to her classmate. She was about to respond to me. Teacher, student, teacher, student. That little ping-pong rally we all know. And the maddening part is, you can have twenty-eight kids in the room and somehow every idea still has to pass through the adult like airport security.

Colin Whitfield

[deadpan] Yes -- the Heathrow model of classroom discussion. Nothing gets through without inspection. And that routing matters because if every contribution comes back to you, students aren't really discussing; they're delivering mini speeches to the examiner. Which is precisely what Topsy Page was trying to fix in her January 23, 2026 post on topsypage.com -- the one titled “ABC: agree, build, challenge.”

Renata Salas

[reflective] Right, and I appreciated that it was so... un-fancy. No glossy acronym pretending to reinvent oxygen. The move is simple: after any student speaks, the next student has to do one of three things on purpose. Agree with the reasoning. Build on the idea. Or challenge it with an alternative. And they actually say those words: “I agree...,” “I’d build...,” “I want to challenge...” It sounds tiny, but it changes who the comment is FOR.

Colin Whitfield

[curious] That phrase “with the reasoning” is doing a lot of work there, isn't it? Because “I agree” on its own is practically content-free. A verbal thumbs-up. But “I agree because...” forces justification. It turns agreement from politeness into evidence.

Renata Salas

Exactly. Otherwise middle schoolers will give you that classic, “I agree with Jayden because... yeah.” [laughs] Nice try, baby, but we're not done. The protocol makes them locate the logic. What exactly do you agree with? The evidence? The inference? The example?

Colin Whitfield

And Page attributes the method to Alex Quigley, who has this lovely phrase -- he says ABC creates “differentiated progress of the highest order.” Which, I'll admit, sounds slightly like something you'd engrave on a very expensive school pen. [dry chuckle] But the idea underneath is actually quite sharp.

Renata Salas

Okay, translate the pen engraving.

Colin Whitfield

[matter-of-fact] Happily. Quigley's point is that the three moves carry different cognitive demands, so more students can enter the discussion without everyone doing the exact same level of mental work at the exact same moment. Agreement is the on-ramp. You're identifying valid reasoning and explaining why it holds up. Building is harder -- now you have to synthesize. You take someone else's idea and extend it, connect it, add evidence, complicate it. Challenge is harder still, because that's evaluation. You're testing the claim against an alternative and justifying why a different reading might be stronger.

Renata Salas

So when he says “differentiated progress,” he doesn't mean low kids do easy work and high kids do hard work forever. He means the structure itself gives different entry points.

Colin Whitfield

Yes -- and importantly, those entry points can shift turn by turn. A student might begin with agreement because that's manageable, then a minute later build on someone else, then eventually challenge. That's the “highest order” bit, I think. Not differentiation by worksheet colour, which always makes me a bit twitchy, but differentiation by thought move.

Renata Salas

[skeptical] See, that I buy more than the usual marketing language. Because in real rooms, “more discussion” is often code for “the same three confident kids talk longer.” ABC is more specific than that. It's not more talking. It's redirecting the traffic so students have to listen sideways, not just forward at the teacher.

Colin Whitfield

“Listen sideways” is good. And that's the hidden mechanism here. If I know my next turn must agree, build, or challenge what YOU said, then I can't simply wait with my own answer loaded in the chamber. I need to track your claim accurately enough to respond to it. That changes attention.

Renata Salas

And it changes accountability. If a kid says, “I want to challenge Maya's point because...,” now Maya exists in the discussion as more than a launchpad for me, the teacher, to say “good thinking.” The students are doing that intellectual handoff themselves.

Colin Whitfield

Which, in fairness, is also slightly terrifying for them at first. And for some teachers. Because once the ball doesn't come back to the adult every time, you've got less control over the neatness of the exchange.

Renata Salas

[laughs] “Less control over the neatness” is the polite British version of “it's gonna get awkward.” And yes. It does. But useful awkward. The first ninety seconds are where you earn the payoff.

Renata Salas

[nostalgic] So here's what this looks like in an actual room, not a conference slide. Before class, you put the stems on the board exactly as written: “I agree with [name] because...”, “I’d build on what [name] said by...”, and “I want to challenge [name]’s point because...” Not summarized. Not implied. Written out. Because when 7th graders freeze, they need the sentence waiting for them.

Colin Whitfield

The exact wording matters there -- “I want to challenge [name]'s point because...” is much safer than the playground version, which is essentially “No, you're wrong.” It critiques the idea, not the child.

Renata Salas

Yes, and you can feel that difference instantly. In my 3rd period, one student answers the opening question, then I call on the next kid and she does that panic-smile thing and starts, “I think that--” and I just point to the board. Not in a gotcha way, just, there it is. Try again. And then she has to force herself into, “I agree with Elena because...” It feels clunky. Everybody hears the training wheels. That's okay.

Colin Whitfield

[questioning tone] “I agree with Elena because...” -- that name, Elena, suddenly becomes the anchor. You're not answering Renata anymore. You're answering Elena.

Renata Salas

Exactly. And that first forced stem is weird in the same way phonics drills are weird. You're being explicit so the move can become automatic later. Usually by the third or fourth turn, I step out a little. I stop choosing every single speaker. Let them self-select. And now the room changes. Kids realize, oh, I can't just polish my own brilliant answer while somebody else is talking. I need something to attach to. Something I genuinely agree with, extend, or push against.

Colin Whitfield

That “third or fourth turn” detail is important. Not immediately -- because then you get chaos -- but not after ten turns either, or the protocol remains teacher-owned. Three or four gives enough modelling, then you release it.

Renata Salas

Right. And the listening burden changes fast. That's the part I think teachers will notice tomorrow if they try it. Students stop listening for “when can I talk?” and start listening for “what can I DO with what was just said?” That's a much more disciplined kind of attention.

Colin Whitfield

Quigley's example on Of Mice and Men captures this beautifully. One student says they'd choose Crooks as a study partner. Then another student builds on that choice. Then a third challenges it and argues for Slim instead. And just in those three moves -- Crooks, build, then Slim -- you begin surfacing the novel's social isolation without the teacher having to swoop in and announce, “Class, the theme is loneliness.”

Renata Salas

[excited] That's the bit I loved. Crooks and Slim are not random names there. If one student defends Crooks, they're probably getting at intelligence, sensitivity, maybe being underestimated. Then when another kid argues for Slim instead, now you've got status, respect, mobility, how power works on the ranch. The class is circling isolation from different angles before the teacher labels it.

Colin Whitfield

And because “Slim” arrives as a challenge to “Crooks,” the thematic contrast is clearer than if the teacher had simply asked, “What is the theme?” Which is often an invitation to vague nouns. Friendship. Loneliness. Society. [dryly] The holy trinity of underdeveloped literary analysis.

Renata Salas

[laughs] Put that on a poster. But seriously, this is why the first ninety seconds are worth the awkwardness. You're teaching the social technology of discussion. Not just hoping it emerges because desks are in a circle.

Colin Whitfield

And one practical point before we go: if a teacher wants to try this tomorrow but doesn't have a good opening question yet, use the tools you've already got. ChatGPT, Claude, MagicSchool, Brisk -- any of them. Ask for one debatable, open-ended question and three follow-ups for your grade, subject, and text.

Renata Salas

But be picky. [skeptical] The prompt can't produce one of those fake-deep questions where everybody obviously agrees. Ask for a question with at least TWO defensible sides and evidence students can point to. That's the phrase I'd use: two defensible sides, evidence in the text. Otherwise there's nothing real to build or challenge.

Colin Whitfield

Yes -- if the question has no friction, ABC becomes ceremonial. Students say “I agree” and “I build” and “I challenge,” but the thinking stays thin. The protocol is only as good as the prompt it sits on.

Renata Salas

[reflective] Which may be the nicest thing about this whole idea. It's not asking teachers to become talk-show hosts. It's asking us to stop being air traffic control for every sentence. Put the stems up. Ask a question worth disagreeing about. Then let the kids do some of the intellectual heavy lifting for each other.

Colin Whitfield

[softly] And if the room feels a bit strange for ninety seconds, that's probably not failure. That's the sound of the ping-pong game ending.

Renata Salas

We'll take that. See you next time.