Making Student Thinking Visible During Number Talks

Let’s be real: one of the trickiest things about running number talks is we never know what students will say. It can feel like flying blind, right? We teachers like to plan, predict, and know all the answers. But number talks are a bit like math improv, and that’s totally okay! Letting go of the need to control every moment is key to making these moments meaningful.

One of the goals of number talks is to help make student thinking visible. But, how do we do that when we’re not sure where their thought process is heading? It’s all about asking the right questions and really listening to how students explain their ideas.

Suppose you are not familiar with number talks and the AMAZING impact they can have on an elementary math classroom. In that case, you can read about them here: Unlocking the Power of Number Talks (an introduction to number talks in an elementary classroom).

In this number talk sample, I worked with my first-grade daughter, who was solving a problem: 8 + 7 + 16. Here’s a play-by-play of how I helped her thinking become visible—not just for her but for other students as well. You can watch the video here and read more about my process below.

@mathhappyhour

One reason number talks can be challenging for teachers is that you don’t know what the kids are going to say. 🤪 It’s hard for us to plan, and that can be scary for teachers. In this video, I am demonstrating how I would do a number talk with my first grade daughter. Part of the video is her explaining how she solved an addition problem mentally, and in the other part, I am showing how I would turn her explanation into a number talk. This is not perfect, but it gives you an example of how you can take a student explaining their thinking and try to capture it in a visual way.

♬ original sound – MathHappyHour

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Step 1: Encouraging Her First Thought

Student: “Eight and seven is 15.”
Me: “Great! How did you know that was 15?”

Before jumping ahead, I wanted her to explain her thinking. She had told me earlier, “I know that eight and eight is 16, so one less is 15.” This is a near-double strategy! Asking her to articulate that helped her understand how she got there and would allow other students to see that there are different ways to think about adding numbers.

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Step 2: Tackling the Next Step

Student: “15 plus 16… let’s see if I take the five and six away.”
Me: “Hmm, how did you know to take away the five and six? Oh, so you’re decomposing the numbers. What two numbers did you decompose 15 and 16 into?”

At this point, she was breaking down 15 and 16, a strategy known as decomposing numbers. I wanted to dig a little deeper to help her clarify her thinking and show other students that this process of breaking down numbers is a smart strategy. She had separated the numbers into tens and ones (15 into 10+5 and 16 into 10+6), leaving her with 10 + 10.

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Step 3: Keeping it Clear

Student: “That would be 10 and 10… so 26.”
Me: “Wait a second, how did you get 26 from 10 and 10? Walk me through that again.”

This is where it gets really important to slow down. I asked her to explain her thinking to keep everything clear. She added the tens first and then brought in the six to reach 26. I crossed out the parts we’d already used, making her process even more visible.

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Step 4: The Final Stretch

Student: “How many if I had 26 and still had five more?”
Me: “What do you think?”

Here, she had to stop and think. I gave her time because thinking time is critical. She broke the five down into four and one, saying, “26 plus four is 30, and then 30 plus one is 31.”

I wanted her to explain how she came to 31 by decomposing the five into smaller parts. Even though she didn’t use the word “decompose,” the important thing was that she did it. She was making sense of numbers in a flexible way.

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Why This Matters

By asking specific questions and giving her space to think, I was able to make her thought process visible not just for her, but for others watching. It’s a reminder that during number talks, our job is to help students articulate their strategies, even when their thinking is messy. That’s how they learn to connect their mental math to paper, making math more understandable and accessible.

Next time you’re doing a number talk, embrace the mess! Ask questions that help students clarify their thinking, and don’t be afraid to let them explore different strategies. You might not always know where their thought process will take you, but that’s the beauty of learning math together.

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Try This Tomorrow!

Next time you’re doing a number talk, take a moment to pause and ask questions like:

• “How did you know that?”
• “Can you explain that step to me again?”
• “What made you think of breaking that number down?”

These small prompts can open up a whole new world of student thinking that you—and their classmates—can see and celebrate!

By focusing on making thinking visible, you’ll empower your students to be flexible and confident with numbers. And that, my friends, is where the math magic happens!

Math Happy Hour Tip: It’s okay to get a little messy during number talks—give yourself permission to let students lead the way and show their thinking, even if it’s different from what you expected!