Which One Doesn't Belong?
Lesson Objective: Make an evidence-supported claim
Grades K-1 / Math / Argumentation

Thought starters

  1. How does this activity look differently in kindergarten and first grade?
  2. How do the teachers ask questions to develop students' understanding?
  3. How are students supported to develop claims?
How I make math calendar for grade 10,11 and 12
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I've ordered the book that another subscriber linked below. Thanks!
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I really liked that the teacher asked the students why do they belong or not belong. Students learn to justify their reasoning for what they believe they see as true or not true. If the students made a questionable guess the teacher then could ask someone else for their ideas and then share what is real to see if everyone then understands .This allows them to see the why which is so helpful in learning. As we all know their is always more than one way to solve a problem so we also need to confirm their ideas so students will continue to participate and be willing to take risks.
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I agree there are incorrect answers, but as educators we want children to take chances and explain why they come up with the answers they do. So if their answer is incorrect we can help show students the correct answers and why.
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Agree...there are indeed incorrect answers...we want children (and teachers alike) to be willing to "risks" and express opinions and back it up with evidence. Let's not fall into the trap, as educators, saying there are no incorrect answers.
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  • Which One Doesn't Belong Transcript

    Speaker 1: I want you to take a look at it and put it in your brain.

    Which One Doesn't Belong Transcript

    Speaker 1: I want you to take a look at it and put it in your brain. What do you see? What do you notice?

    Speaker 2: Let's hear some of the things that you were noticing, really quickly, okay?

    Speaker 3: I noticed that they have pointy sides.

    Speaker 4: The idea is for the students to be looking at a group of objects and being able to decide, well, which one doesn't belong and being able to give a reason why or why not.

    Speaker 2: Mathematicians, are you ready?

    Speaker 5: Yeah.

    Speaker 2: All right.

    Speaker 6: Which one doesn't belong is an activity where the kids look at four different shapes, and in those shapes they're looking for similarities, differences, in order to formulate an argument and justify that argument. The students had to reason through the shapes and think about what they noticed first.

    Speaker 2: Leah, what are you noticing?

    Leah: I notice that all pointy and different shapes.

    Speaker 2: All pointy and different shapes. Great.

    Leah: I notice that that one looks like a heart and that one looks almost like a heart.

    Speaker 2: Wow, all right. Thank you for all of your great noticings.

    Speaker 8: That one's green.

    Speaker 9: Which one? Oh, the apple is green, yes. Kamora?

    Kamora: There is bananas.

    Speaker 9: Yes.

    Speaker 2: Now I have another question for you, and this one I'm going to want you to share with the person next to you, so I want you to turn and talk and share with the person next to you. Which one of these belong together?

    Speaker 5: [crosstalk 00:01:37] I think that one and that one are the same.

    Speaker 2: Okay, a lot of great ideas. Eva.

    Eva: I think all of them belong together, because they're all the same color.

    Speaker 2: Wait a second. Do you remember what to do? Do you remember what you have to do? You got to come teach us.

    Eva: All these belong together because they're all the same colors.

    Speaker 2: They all belong together because they're the same colors. Thank you. I also want to compliment Eva for coming up in front of the class like a teacher. She turned her body, she was facing towards us, did a really nice job of that. Thank you.

    Speaker 12: I think these two belong because they're almost the same.

    Speaker 2: Why are they almost the same? You said almost.

    Speaker 12: Because this one is a heart and this one is spikes, has pointy spots.

    Speaker 2: Uh-huh.

    Speaker 13: I think this one, this one, and this one, because they have curvy sides.

    Speaker 14: The apple goes with ... I think it's salad, because they're both green.

    Speaker 2: Oh.

    Speaker 1: Can someone repeat what Tomas said. Alice, what did he say?

    Alice: He said that the apple and that vegetable is like lettuce, because it's both green.

    Speaker 1: That's a good idea. If you agree with that, let's give him a "me too" and an "I agree." Good thinking, and also, he put it all together. He said the apple ... We're going to call this lettuce, and the lettuce belong because they're both green. He said because. He gave a why.

    Speaker 16: It offers students this great opportunity to really practice making arguments, saying their idea and supporting that idea, and it also sends larger messages about what it means to talk in math class, in terms of listening to each other's ideas, supporting your claims, and it's not just about arriving at one answer and calling it done, that we can keep generating ideas and keep looking for other properties of the four objects.

    Speaker 1: Now I have another question. We talked about what we noticed, which is just what we see. Your next job, you're going to talk to your partner about it, is to decide which three would you put together, and which would one would you say it doesn't belong, it doesn't go with the group.

    Speaker 16: The beauty of it is that it's open-ended, there are no wrong answers, but they need to be able to say why they think a certain object doesn't belong. In this case we had three fruits and a vegetable, but there was a color variant, there was a more than one variant, so there were different ways to look at why one wouldn't belong.

    Speaker 17: I think the grapes doesn't belong because it's all purple.

    Speaker 18: The lettuce don't belong and three of fruit belong.

    Speaker 1: Oh, that is such a good idea, and the three fruits ...

    Speaker 18: Belong.

    Speaker 1: They belong.

    Speaker 19: I think those two don't belong, because they're different shapes and those hearts are like, that pointy one is look like a heart, and that beautiful is like a heart.

    Speaker 2: Yeah, you're noticing a lot. Thank you.

    Speaker 20: These two does not go together. This one don't have a circle, and this one had circle.

    Speaker 2: Why does this one not belong?

    Speaker 21: Because there's ... Look at, it don't have pointy sides, and it don't changes, and it's got circles there, but these one don't have it.

    Speaker 2: Wow, okay, thank you.

    Speaker 5: It creates a-ha moments, where a student will share an idea and you'll hear it ripple across the room on the carpet, with kids going "Oh," and suddenly that idea begins to take off. It allows kids to be able to hear and then also build upon their ideas.

    Speaker 2: It sounds like we've had Britney and Euzra come up and talk about those three.

    Speaker 22: I think that these three go together, because they're one shape and this is two shapes together, because the square and circles.

    Speaker 2: Okay. Can you tell us that again, please?

    Speaker 22: I think these three belong, because these are one shape but this is two shapes.

    Speaker 2: Okay, so you think it's these three? Is that right?

    Speaker 22: Yeah.

    Speaker 2: Okay.

    Speaker 16: Trying to make sense of things, articulating our thinking, backing up our claims, engaging with other people's ideas, those are how people use math in the real world, and so we need to support young learners to engage with mathematics that way from the very beginning, and five and six year olds are absolutely capable of doing so with the right activity structures and the right supports.

    Speaker 2: I see people notice that these three all have curves. We notice that, Cristiano talked about this one having what?

    Speaker 5: Two shapes.

    Speaker 2: Two shapes, these one not. All right, excellent job, mathematicians.


Donella Oleston
Ryan Reilly


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