Latest / Rounding Up / Which One Doesn't Belong Routine with Dr. Christopher Danielson
Transcript
- 0:03The idea of comparing items and looking for similarities and differences has
- 0:08been explored by many math educators that said,
- 0:11Christopher Danielson has taken this idea to new heights inspired by Sesame
- 0:16Streets. One of these things is not like the others. Christopher wrote the book,
- 0:20which one Doesn't Belong? In this episode,
- 0:23we'll ask Christopher about the which one doesn't belong routine and the
- 0:26features that make it such a powerful learning experience for students.
- 0:33Welcome to the podcast, Christopher. I'm excited to be talking with you today.
- 0:37Thank you for the invitation. Delightful to be invited.
- 0:40I would love to chat a little bit about the routine, which one doesn't belong.
- 0:44So I'll ask a question that I often will ask folks, which is,
- 0:47if I'm a listener and I don't have prior knowledge of that routine,
- 0:52how would you describe it for someone?
- 0:54Yeah.
- 0:55Sesame Street back in the day had a routine called Which one Doesn't Belong.
- 0:59There was a little song that went along with it, and for me,
- 1:02the iconic Sesame Street image is Grover is on the
- 1:06stairs up to the brownstone on the Sesame Street set,
- 1:10and there are four circles drawn in a two by two grid in chalk on the wall.
- 1:14And there are a few of the adults and a couple of the puppets sitting around and
- 1:18they're asking Grover and singing the song, which one of them doesn't belong.
- 1:20There are four circles, three of them are large and one is small,
- 1:24or maybe it's the other way around. I don't remember.
- 1:26So there's one right answer, and Grover is thinking really hard,
- 1:31think real hard as part of the song they're singing to him,
- 1:33he's under a lot of pressure to come up with which one doesn't belong in.
- 1:37Fortunately, Grover Succeeds, Grover's a hero,
- 1:39but what we're wanting kids to attend to, there is size.
- 1:43There are three things that are the same size. All of them are the same shape,
- 1:47three that are the same size, one that has a different size.
- 1:49They're wanting to attend to size. Lovely.
- 1:51This one doesn't belong because it is a different size,
- 1:54just like my underwear doesn't belong in my socks drawer
- 1:59because it has a different function. I mean, it's not for me. There is,
- 2:04we could talk a little bit about this in a moment.
- 2:06The belonging is in that mathematical and everyday sense of objects and whether
- 2:11they belong.
- 2:12So that's the Sesame Street version through a long chain of math
- 2:17educators.
- 2:18I came across a sort of tradition that had been flying
- 2:22along under the radar of rethinking that with the idea being that
- 2:27instead of there being one property to attend to,
- 2:30we're going to have a rich set of shapes that have rich and interesting
- 2:34relationships with each other. And so which one doesn't belong?
- 2:36Depends on which property you're attending to.
- 2:40So the first page of the book that I published called, which one Doesn't Belong,
- 2:44has four shapes on it. One is an equilateral triangle standing on a vertex.
- 2:49One is a square standing on a vertex. One is abus,
- 2:53a non square rhombus standing on its vertex and it's not colored in.
- 2:56All the other shapes are colored in.
- 2:57And then there is the same non square thrombus colored in, resting on a side,
- 3:03all sort of simple shapes that offer
- 3:08simple introductory properties,
- 3:11but different people are going to notice different things.
- 3:13Some kids will hone in on that.
- 3:15The one in the lower left doesn't belong because it's not colored in.
- 3:17Other kids will say, well,
- 3:19I'm counting the number of sides or the number of corners.
- 3:22And so the triangle doesn't belong because all the others have four and it has
- 3:24three. Others will think about angle measure, they'll choose a square.
- 3:27Others will think about orientation.
- 3:29I've been taken a task by a couple of people about this.
- 3:31Kindergartners are still thinking about orientation as one of the properties.
- 3:35So the shape that is in the lower right on that first page is a rhombus resting
- 3:39on a side instead of on a vertex.
- 3:41And kids will describe it as the one that feels like it's leaning over or that
- 3:44has a flat bottom or it's pointing up into the right and all the others are
- 3:48pointing straight up and down. So that's the routine.
- 3:51And then things as with how did you count as with how many?
- 3:54As you page your way through the book, things get more sophisticated.
- 3:58And for me, the entry was a geometry book because when my kids were small,
- 4:02we had sort of these simplistic shapes books,
- 4:04but really rich narrative stories in picture books that we could read. And it
- 4:08was always a bummer to me that we'd read these rich stories about characters
- 4:12interacting. We'd see how their interactions,
- 4:14their conflicts relate to our own lives,
- 4:16and then we'd get to the math books and it would be like triangle,
- 4:18always equilateral, always on a side square,
- 4:21never a square on the rectangle page.
- 4:23Rectangle gets a different page from square.
- 4:25And so we understand culturally that children can deal with and
- 4:30are interested in and find fascinating and imaginative rich narratives,
- 4:34but we don't understand as a culture that children also have rich math minds.
- 4:37So for a long time I wanted there to be a Better Shapes book and there are some
- 4:41better shapes books. They're not all like that,
- 4:43but they're almost all like that.
- 4:45And so I had this idea after watching one of my colleagues here in Minnesota,
- 4:48Terry Weiberg, this routine, he was doing it with fractions,
- 4:52but about a week later I thought to myself, Hey, wait a minute,
- 4:54what if I took Terry's idea about there not being one right answer,
- 4:57but any of the four could be and combine that with my Wish for a Better Shapes
- 5:01book. And along came which one doesn't belong as a Shapes book.
- 5:04So there's a square and a rectangle on the same page.
- 5:06There are shapes with curvy sides and shapes with straight sides on the same
- 5:10page and kids have to wrestle with or often do wrestle with what does it mean to
- 5:14be a vertex or a corner?
- 5:16A lot of really rich ideas can come out of some well chosen simple examples.
- 5:20I chose to do it in the field of geometry,
- 5:22but there are lots of other mathematical objects as well as non mathematical
- 5:25objects. You could apply the same mathematical thinking too.
- 5:28So I think you have implicitly answered the question that I'm going to ask.
- 5:32If you were to say at the broadest level,
- 5:35regardless of whether you're using shapes, numbers,
- 5:39images,
- 5:40whatever the content is that an educator selects to put into the two by
- 5:45two, that is structurally the way that which one doesn't belong is set up,
- 5:50what's it good for?
- 5:52What should a teacher think about in terms of this will help me or will help my
- 5:56students? Fill in the blank.
- 5:59How do you think about the value that comes out of this?
- 6:02Which one doesn't belong structure and experience.
- 6:05Multidimensional for me,
- 6:07I don't know if I'll remember to say all of the dimensions,
- 6:10so I'll just try to mention a couple that I think are important.
- 6:13One is that I'm going to make you a promise that whatever mathematical ideas you
- 6:16bring to this classroom during this routine are going to be valued.
- 6:20The measure of what's right,
- 6:22what counts as a right answer here is going to be what's true,
- 6:26not what I thought of when I was setting up this set.
- 6:29I think there is a lot of power in making that promise and then in
- 6:34holding that promise, it is really, really easy.
- 6:38All of us have been there as teachers that we make an instructional promise to
- 6:41kids that then there comes a time where it either inadvertently or we make a
- 6:45decision to break that promise.
- 6:47I think there's a lot of costs to that. I know from my own experience as a
- 6:50learner,
- 6:51from my own experiences as a teacher that there can be a high cost to that.
- 6:55So valuing ideas, I think this is a space I love having.
- 6:59Which one doesn't belong as a time that we can set aside for the measure of
- 7:02what's right is what's true.
- 7:03So when children are making claims about this one in the upper right doesn't
- 7:06belong, I want you to for a moment try to think like that person,
- 7:11even if you disagree, that that's important.
- 7:13And so teachers have to play that role. Also. Where that comes up a lot is in,
- 7:18especially when I'm talking with adults,
- 7:19if I'm talking to parents about which one doesn't belong,
- 7:22often parents who don't identify as math people or who explicitly identify as
- 7:26non-math people will say that one in the lower left,
- 7:30it's not colored in. But I don't think that really counts in that moment.
- 7:35Kids are less likely to make that apology,
- 7:36but adults will make that apology all the time.
- 7:38And in that moment I have to both bring the adult in as a mathematical thinker,
- 7:41but also model for them what does it look like when their kid chooses something
- 7:46that the parent doesn't think counts. So for me,
- 7:49the real thing that which one doesn't belong is doing is teaching children,
- 7:54giving children practice and expertise,
- 7:57therefore learning about a particular mathematical practice,
- 8:00which is abstraction that when we look at these sets of shapes,
- 8:04there are lots of properties. And so we have to for a moment,
- 8:08just think about number of sides, and if we do that,
- 8:11then the triangle doesn't belong because of the other four.
- 8:13But as soon as we shift the property and say, well,
- 8:16let's think about angle measures,
- 8:18then the ways that we're going to sort those shapes the relationships that they
- 8:21have with each other changes. And that's true with all mathematical objects.
- 8:25And you can do that kind of mathematical thinking with non mathematical objects.
- 8:29One of my favorite, which one doesn't belong sets,
- 8:32is there's a donut chocolate donut. There's a coffee cup,
- 8:36one of those speckled blue camping metal coffee cups.
- 8:39There's half a hamburger bun with a bunch of seeds on top and then there is a
- 8:42square everything bagel. And so as kids start thinking about that, they're like,
- 8:47well, if we're thinking about holes, the hamburger bun doesn't have a hole.
- 8:50If we're thinking about speckling, the chocolate donut isn't speckled.
- 8:53If we're thinking about whether it's an edible substance,
- 8:55the coffee cup is not edible. And so that's that same abstraction.
- 9:00If we pay attention to just this one property that forces a sort,
- 9:03if we pay attention to a different property,
- 9:05we're going to get a different sort. And that's one of the practices of
- 9:08mathematicians on a regular basis.
- 9:10So regular that often when we're doing mathematics,
- 9:14we don't even notice that we're doing it.
- 9:16We don't notice that we're asking kids to ignore all the other properties of the
- 9:20number two except for its evenness right now. If you do that,
- 9:23then two and four are like each other.
- 9:26But if we're supposed to be paying attention to primally as to a prime number,
- 9:30then two and four are not like each other. All mathematical objects,
- 9:34all mathematicians have to do that kind of sort on the objects that they're
- 9:37working with.
- 9:37I had a college algebra class at the community college while I was working on
- 9:42which one doesn't belong.
- 9:43And so I was test driving this with graphs and my students.
- 9:47I could still see Rosalie in the middle of the room room full of 45 adults
- 9:51ranging from 17 to 52. And I'm this 45-year-old college instructor,
- 9:56and we have three parabola and one absolute value function.
- 10:00So parabola y equals X squared.
- 10:02It's that nice curving swooping thing that goes up at one end down to a nice
- 10:05bowl and then up again, there's one that's upside down.
- 10:08I think there's one pointing sideways.
- 10:10And then an absolute value function is the same idea,
- 10:12except it's two lines coming together to make a bowl sort of a very sharp bowl
- 10:16instead of being curves. And we got this lovely, which one doesn't belong,
- 10:19right?
- 10:20So we've got this lovely collection of them and Rosalie like her eyebrows are
- 10:23getting more and more knitted as this conversation goes on.
- 10:26So finally she raised her hand, I call on her and she says, Mr. Daniels,
- 10:31and I get that all of these things are true about these,
- 10:35but which ones matter,
- 10:37which is a fabulous question that within itself holds a lot of tensions
- 10:41that Rosalie is used to being in math class and being told what
- 10:46things she's supposed to pay attention to. And so in some ways it's sort of
- 10:49disturbing to have me up there and I get that up there front of the classroom
- 10:54valuing all these different ways of viewing these graphs because she's like,
- 10:57which one is going to matter?
- 10:58When you ask me this question about something on an exam,
- 11:03which ones matter? But truly,
- 11:05the only intellectually honest answer to her question is, well, it depends.
- 11:10Are we paying attention to direction of concavity?
- 11:13Then the one that's pointing sideways doesn't count any one of these is it
- 11:17depends on whether you're studying algebra or whether you're studying geometry
- 11:20or topology. And I did give her, I think,
- 11:23I hope what was a satisfying answer after giving her the true but not very
- 11:27satisfying answer of it depends, which is something like, well,
- 11:31in the work we're about to do with absolute value functions,
- 11:34the direction that they open up and how steeply they open up are going to be the
- 11:37things that we're really attending to and we're not going to be attending as
- 11:40much to how they are or not like parais,
- 11:42but seeing how they have some properties in common with these parais is probably
- 11:46going to be really useful for us.
- 11:48That actually makes me think of one,
- 11:49a statement of what I think is really powerful about this. And then two,
- 11:53a pair of questions that I think are related.
- 11:56It really struck me Rosalie's question how different the
- 12:00experience of engaging with a,
- 12:02which one doesn't belong is from what people have traditionally considered math
- 12:07task where there is in fact an answer, right?
- 12:11There's something that the teacher's like, yep, that's the thing.
- 12:14Even if it's perhaps obscured by the task at first,
- 12:18ultimately oftentimes there is a thing and a which one doesn't belong is a very,
- 12:23very different type of experience.
- 12:25So that really does lead me to two questions.
- 12:28One is what is important to think about when you're facilitating A,
- 12:33which one doesn't belong experience?
- 12:35And then maybe even the better question to start with is what's important to
- 12:39think about when you're planning for that experience?
- 12:42Facilitating is going to be about making a promise to kids.
- 12:45That measure of what's right is what's true.
- 12:48I'm interested in the various ways that you're thinking and doing all the kind
- 12:52of work that we discussed, but now in this context of geometry,
- 12:54or in my case in the college algebra classroom,
- 12:58in the context of algebraic representations planning,
- 13:02I have been so deeply influenced by the work of
- 13:07Peg Smith and her colleagues and the five practices for facilitating
- 13:11mathematical conversations. And in particular,
- 13:14I think in planning for these conversations, planning a set,
- 13:18when I'm deciding what shapes are going to go in the set or how I'm going to
- 13:20arrange the eggs and the egg carton,
- 13:22or how many half avocados am I going to put on the cutting board?
- 13:26I'm anticipating one of those practices.
- 13:28What is it that kids are likely to do with this? And if I can't
- 13:32anticipate anything interesting that they're going to do with it,
- 13:35then either my imagination isn't good enough and I better go try it out with
- 13:39kids,
- 13:40or my imagination is absolutely good enough and it's just kind of a junkie thing
- 13:44that's not going to take me anywhere and I should abandon it. So over time,
- 13:48I've gotten so much better at that anticipating work because I have learned,
- 13:53I've become much more expert at what kids are likely to see.
- 13:56But I also always get surprised in a sufficiently large group of kids,
- 13:59somebody will notice something or have some way of articulating differences
- 14:04among the shapes.
- 14:05Even these simple shapes on the first page that I haven't encountered before,
- 14:08and I get to file that away again for next time.
- 14:10That's learning that gets fed back into the machine,
- 14:12both for the next time I'm going to work with a group of kids,
- 14:14but also for the next time I'm sitting down to design an experience.
- 14:18You have me thinking about something else,
- 14:21which is what closure might look like in an experience like this.
- 14:24Because I'm struck by the fact that there might be some really intentional
- 14:28choices of the items in the which one doesn't belong.
- 14:31So the four items that end up being there,
- 14:34it may be designed to drive a conversation around a set of properties or a set
- 14:38of relationships,
- 14:40and yet at the same time be open enough to allow lots of kids to be right in the
- 14:45things that they're noticing. And so if I've got a which one doesn't belong,
- 14:49that kind of is intended to draw out some ideas or have kids notice some of
- 14:52those ideas and articulate them, what does closure look like?
- 14:56Because I could imagine you don't know what you're going to get necessarily from
- 15:01kids when you put a, which one doesn't belong in front of them.
- 15:03So how do you think about different ways that a routine or experience like this
- 15:07might close for a teacher and for students?
- 15:10Yeah,
- 15:10I think one of the best roles that a teacher can play at the end of a which one
- 15:15doesn't belong conversation is going back and summarizing the
- 15:19various properties that kids attended to.
- 15:22Because as they're being presented and maybe annotated,
- 15:25we're noticing them sort of one by one,
- 15:27and we might not have a moment to set them aside.
- 15:30It might take a minute for a kid to draw out their ideas about the orientation
- 15:34of this shape,
- 15:35and it might take a little bit and some clarification with another kid about how
- 15:39they were counting sides.
- 15:40They might not have great words for sides or corners and it's gestures and we're
- 15:44all trying to figure things out. And so by the time we figured that out,
- 15:46we've forgotten about the orientation answer that we had before.
- 15:49So I think a really powerful move,
- 15:51one of many that are in teachers' toolkits is to come back and say, all right,
- 15:55so we looked at these four shapes and what we noticed is that if you're paying
- 15:59attention to how this thing is sitting on the page to its orientation,
- 16:04which direction it's pointing,
- 16:05then this one didn't belong and Susie gave us that answer. And then another
- 16:10thing you might pay attention to, another property could be the number of sides.
- 16:14If you're paying attention to the number of sides the triangle doesn't belong,
- 16:16and we got that one from Brent, right?
- 16:17And so run through some of the various properties.
- 16:20Also noticing along the way that there were two reasons to pick the triangle as
- 16:25the one that doesn't belong. It might be the sides,
- 16:27and it might be you might have some other reason for picking it.
- 16:29That isn't the number of sides for kindergartners,
- 16:32the number of corners or vertices,
- 16:36and the number of sides are not yet obviously the same as each other.
- 16:39So for a lot of kindergartners that feels like two answers rather than one.
- 16:43Older audiences are more likely to know that that's going to be the same.
- 16:47So yeah,
- 16:47I think the being able to come back and state succinctly after we've had this
- 16:51conversation, valuing each of the contributions that came along,
- 16:54but also being able to compare them. Maybe we're writing them down as part of
- 16:57our annotation. There might be other ways that we do that.
- 17:00But I think summarizing so that we can look at this set of ideas that's been
- 17:03brought out altogether, I think is a really powerful way.
- 17:06One other quick thing about designing, which is I hear this a lot from teachers.
- 17:11They're saying, okay, so we're studying quadrilaterals. So I made a,
- 17:14which one doesn't belong with four quadrilaterals?
- 17:16And nobody noticed that they were all quadrilaterals,
- 17:19to which I say they didn't notice because you didn't contrast that property.
- 17:22So if there's a property you want to bring out,
- 17:24you better make sure I think that you have three things that have it and one
- 17:28that doesn't, or vice versa, three that don't, and one that does,
- 17:31because then that's a thing for kids to notice.
- 17:33They're not going to notice what they all have in common.
- 17:36That's not the task we're asking them.
- 17:37So if you want to make one about Quadrilaterals, throw a Pentagon in there.
- 17:41Love it.
- 17:42So the question that I typically will ask any guest before the close of the
- 17:46interview is,
- 17:47what are some resources that might grab onto be they yours
- 17:51or other work in the field that you think is really powerful that supports the
- 17:55kind of work that we've been talking about?
- 17:57What would you offer to someone who's interested in continuing to learn and
- 18:00maybe to try this out?
- 18:01So we've referred to number talks. That talks and number talks.
- 18:05Those are both phrases that can be Googled. There are three books,
- 18:08which one Doesn't Belong? How Did You Count? All published by Stenhouse,
- 18:12all available as a hardcover book,
- 18:15hardcover student book or home picture book.
- 18:18So for listeners, just so you know,
- 18:20we're going to add links to the resources that Christopher referred to in all of
- 18:23our show notes for folks Convenience. Christopher,
- 18:26I think this is probably a good place to stop. Thank you so much for joining us.
- 18:29It's absolutely been a pleasure chatting with you.
- 18:31Yeah, thank you for the invitation for your thoughtful prep work and
- 18:36support of both the small and the larger projects along the way.
- 18:40I appreciate that.
- 18:41I appreciate all of you at Bridges and the Math Learning Center.
- 18:44You do fabulous work.
- 18:46This concludes part one of our discussion with Christopher Danielson.
- 18:50Christopher is going to join us again later this season where we'll have a
- 18:53conversation about the nature of counting and how an expanded definition of
- 18:58counting might help support students later in their mathematical journey.
- 19:02I hope that you'll join us for this conversation.
- 19:08This podcast is brought to you by the Math Learning Center and the Meyer Math
- 19:11Foundation dedicated to inspiring and enabling all individuals to
- 19:16discover and develop their mathematical confidence and ability.