Showing posts with label math. Show all posts
Showing posts with label math. Show all posts

Tuesday, October 7, 2014

Remainders: The Rest of My Interview with Steven Strogatz



Response to the Atlantic article, "Teaching Math to People Who Think They Hate It," a look into Steve Strogatz's adventures teaching math to liberal arts majors at Cornell, has been lovely. I've received a couple of emails asking for more information about Discovering the Art of Mathematics, Julian Fleron and his team at Westfield State, so Steve and I thought it might be fun to post the rest of our interview, as well as a link to the scalene triangle straight-cut origami exercise described in the article (Chapter 3 of Discovering the Art of Mathematics: Art and Sculpture).

Steve is a great interview; he loves what he does, and has a knack for explaining the details of that love to other people. I hated having to cut anything he said, but in order to make my word count, I had to chop, chop, and snip, snip.

If you'd like to read Steve's work, and you have not read his "Elements of Math" series in the New York Times, I highly recommend that series of essays as a starting place. Be sure to start with the first one, "From Fish to Infinity." You can also hear him in his regular appearances on Radiolab.

And with that, here's the rest of our interview, with a few liberties made for the sake of clarity.
  


Lahey: What prompted you to teach mathematics to liberal arts majors?

Strogatz: For the past few years I've been growing dissatisfied with the results of my usual way of teaching, which is lecturing. Although quite a few of my students seemed to enjoy my lectures, many of them weren't engaging with the material deeply. Just watching a performance, a lecture, and then doing homework, wasn't enough to get them to learn the subject properly, to master it.

So I’d been toying with the idea of trying some more active form of teaching and learning, but I wasn't sure how to start. One day when I was at the big annual math meeting – the “Joint Mathematics Meetings” where the major mathematical societies come together in January – I was wandering around in the exhibition hall and came across an exhibit that caught my eye. There were three or four young professors from Westfield State who were encouraging people to play math games. They were handing out Rubik's cubes, getting people to play a game called hex, or tying knots, or even dancing and making knots with their own bodies in groups. When I took a closer look I noticed that they had workbooks strewn over their table. These were workbooks that they themselves had written for a "math for liberal arts" course that they'd been teaching for the past few years at Westfield State. These workbooks were so attractive, and so filled with interesting activities for students to do, that I started to think this could be a way for me to try teaching in a style where my students would be more active.

When I talked with these faculty from Westfield State, I was struck by their passion for what they called inquiry-based learning. I found myself coming back to their exhibit, over and over again, over the next few days. I kept bringing other colleagues over to their booth to show them what was going on, to show them how cool and exciting it was. Something about it grabbed me.

And I guess what really clinched it was when Julian Fleron, one of the faculty from Westfield State, told me that they had a grant from the National Science Foundation to spread their ideas widely through the math community, and that they would be delighted to come to Cornell to give us a workshop, to show us how to make this style of teaching a reality in our courses. That was an offer I couldn't refuse. So when the time came to choose courses for this year, I asked to teach a course that was already on the books at Cornell called "Mathematical Explorations." It turns out that a course in this active style of learning, this inquiry-based learning, already existed at Cornell and had been taught for a number of years. But I had only recently joined the math department, having spent the first 20 years of my career at Cornell in engineering. So the course was new to me. I asked to teach it.

In mid-August the Westfield State folks came to visit us and give us that workshop. They showed us how to teach in this style, and how to assess our students’ performance, and also how to approach some of the psychological issues that come up with this population of students, issues like math anxiety and math phobia. They also showed us what it would feel like to be a student in such a class. My Cornell colleagues and I were the students, doing a paper-folding-and-cutting game; the Westfield State folks were our teachers. That was important since none of us had ever been students in an inquiry-based learning classroom. We needed to know what it felt like, to have the right kind of empathy for our students.


Lahey: Your usual fodder, as evidenced by your Twitter feed, is higher math. Do you find teaching a more...elementary level of math interesting? 

Strogatz: Yes, I find it fascinating and thrilling. This population of students is unlike any I've ever taught before. The course I’m teaching fulfills our "mathematics and quantitative reasoning" requirement at Cornell. That's a requirement to ensure that all students in the College of Arts and Sciences are exposed to some minimal amount of mathematical thinking. As it turned out more than half of the students in my class of about 36 are seniors. In other words, they have been putting off this requirement for as long as they possibly could!

It's what you might imagine – these are students who have had some unpleasant experience with math at some point in their education. For the first assignment I asked them to write their mathematical autobiography, detailing experiences that they had both good and bad in their math education up to this point. I also wanted to hear about any teachers who made an impression on them, positively or negatively, and what other subjects they're interested in and so on. I'm still reading through some of those autobiographies now but what's emerging is that many of the students liked math for several years. These are all very bright students but somewhere along the line they got discouraged. Sometimes it was because of a certain teacher or subject. In other cases everything was fine through high school, but when they took calculus at Cornell, something about that class turned them off.

As for teaching at a more elementary level, well, first of all, math is interesting at every level. Elementary school math is just as interesting as middle school, high school, college, or graduate level math. I love thinking about the fundamentals! So the elementary nature of the subject is not an issue.

Besides, what we’re exploring in this class is not particularly elementary! This week, for example, the week that you're visiting, we’ll be investigating ideas in abstract algebra (in the particular, the subject known as group theory) but we’ll be doing it in an unusual way (at least, unusual for a math class): we'll use dance to explore symmetry. Dance may be a bit of an inflated word for what we’re doing (in fact, I was a little intimidated to start teaching about dance, since I'm such a lousy dancer myself). What we’re doing is more like striking a pose. Or moving very slowly from pose to pose, while a partner tries to follow the leader in mirror-image symmetry, or rotational symmetry, or some other type of symmetry.

I have to say that teaching this class has been a joyful experience in a way that no other class I've ever taught has been. I love teaching, and I certainly love teaching students who already enjoy math – don't get me wrong. But there's something remarkable about working with a group of students who think they hate math or find it boring, and then turning them around, even just a little bit.

For example, the first activity that we worked on was what's known as “straight-cut origami.” Imagine a simple shape, say an equilateral triangle, drawn on a piece of paper. The goal is to cut out the triangle with scissors. Except that you're not allowed to cut out the triangle in the obvious way. Instead you have to fold the paper in such a way that you can cut out the triangle by making a single straight cut. For an equilateral triangle this turns out to be pretty easy and everyone can do it. But if you pick a general triangle – a scalene triangle, meaning one where all three sides are different lengths – then figuring out how to fold the paper in such a way that you can cut out the triangle with a single straight cut turns out to be very difficult. Or, at least, not obvious. I had trouble with it myself for quite a while the first time I tried it.

So while we were working on this in class, with the students seated at tables of four, all discussing the problem, showing each other their ideas, things that had worked or not worked, after they struggled with this for about a half-hour it turned out that only one student out of 36 was able to do it. So at the end of the class, when I noticed that there were only about five minutes left I asked "Would you like a hint?" A few students immediately said yes, but then they were drowned out by the rest of the class, which said no!

I was so proud of them. They were having a true mathematical moment. That is, they were deeply engaged with a puzzle that made sense to them, and they were enjoying the struggle, and no, they did not want a hint! They were feeling what anyone who loves math feels, the pleasure of thinking. The pleasure of wrestling with a problem that fascinates you. No one in the class was asking, “what is this good for?” Or "where will I ever use this?” Those are questions that students ask only when they are not engaged.

I told the students to think about the scalene triangle over the weekend and to try it in their dorm room. Over the weekend I started to get emails from some of them expressing the excitement they felt when they solved it. One student wrote: “I am feeling exceptionally accomplished. I have to admit: this math assignment has made my day. I never thought I would ever be saying this.”

Lahey: There has been a lot of talk lately about approaches to teaching math, particularly as it relates to the Common Core State Standards. Do you have any thoughts about the "critical thinking" approach versus the traditional route toward mathematical fluency via math facts and rote execution of concepts?

Strogatz: On the whole I think we usually go too fast in our teaching of math. There's a big rush to cram all kinds of information into the students’ heads, and get them fluent with certain procedures, at the expense of their understanding what they're doing.

But let me be careful here. It's so easy to cast this discussion in black and white terms, to make one point of view seem ridiculous and the other obvious. I don't want to do that, because of course you need to memorize certain things and of course you need to have an understanding of what you're doing.

It'll probably sound like a wishy-washy answer, but I really want both. I want my students to memorize and know basic facts, and I want them to understand what those facts mean, why they're important, where they come up in the real world, how to calculate efficiently and easily with them, how they developed historically, what their connections are to the arts and humanities and sciences and engineering, where they pop up in daily life and in the universe. I want it all and I think students want it all too.

If we just stick to teaching them rote procedures, math becomes meaningless. That's how it's experienced by many people. So I'm definitely against that.

But likewise if we only teach conceptual approaches to math without developing skill at actually solving math problems, students will feel weak. Their mathematical powers will be flimsy. And if they don't memorize anything, if they don't know the basic facts of addition and multiplication or, later, geometry or still later, calculus, it becomes impossible for them to be creative. They can't take the first step, because they have to rely on their graphing calculator, or look something up in a book. That makes for a student who can never achieve the greatest pleasure or success in math, which is to be inventive, to think of things for yourself. It's like in music. You need to have technique before you can create a composition of your own. But if all we do is teach technique, no one will want to play music at all.

Nothing I'm saying here is very radical or surprising to anyone who actually understands mathematics (or any other creative endeavor). If you want to be a great soccer player, you can't just do drills. You won't even want to play soccer if you're just doing drills all day. You have to get out there and play the game, and learn from your mistakes and then practice. Drills have their place, and so does playing the real game.

We do too much drilling in school, and not enough playing of the real game of math. And as with any game, or playing music or making a piece of art, it's doing the real thing that's inspiring. We need to give students more of a chance to do that. And that’s what I'm trying to do in this class. They are actually making mathematics -- in many cases, for the first time in their lives. And they’re loving it. And why wouldn't they? It’s a joyous, glorious experience. At every level. Little kids can make math. It may be the mathematical equivalent of fingerpainting, but it’s still math. Genuine creativity is required at every level.

Monday, July 30, 2012

On Critical Thinking, Algebra, and Math Anxiety

Today marks a first for me: I have two pieces running in two different sections of The New York Times on the same day!

Over at The Learning Network, the first of a week-long series of critical thinking questions is up for reader consideration. My editor at The Learning Network, Katherine Schulten, has asked readers to let her know whether or not they like my questions, and if enough people are excited about them, I get promoted to weekly feature status. So come on over, take the critical thinking quiz, and submit your feedback to Katherine.

At Motherlode, I weigh in on Andrew Hacker's opinion piece about the necessity of algebra in American education. My response is personal, rather than policy-based, and comes out of my recent return to Algebra I.

I am reposting the first of my posts about going back to math class below, and for my further adventures in Algebra I, read "Algebra I: Still Hazy After All These Years," "Exponents, Products, and [my mathematical] Powers" and "Exponent Negativity."


Quantifying the Unknown



I have a recurring dream: I am in college, or law school - sometimes high school - and I have not attended classes all semester. I don't know where my locker is, let alone the combination, and I'm not sure where the classrooms are. I certainly don't know what material we have covered. It's exam time, and I know I won't even be able to find the classroom so I can take the exam. I know that if I don't pass the exam, I will not be able to graduate, so I have to find the main office and I can ask them where my classes are. I wander around the school, often in that slow, stunted, underwater way, and get nowhere as the minutes of the exam period tick by.

One fun twist on last night's version of the dream is that while I was digging around in my materials, looking for any clue as to my class schedule, I found an application for an internship with Billy Collins. Despite that nice surprise, I still woke up nervous and flummoxed.

The class I fail in my dreams is usually math, which is absolutely predictable if you know me at all. I have never done well in math, and as a result, I have serious math anxiety. I can grade papers and calculate percentages, but anything more complex than that brings on the shakes. So when I woke up this morning at 4:32 A.M., drenched in sweat, I decided to return to the place of my defeat (again) and go back to school.

Fortunately, the math teacher at my school is amazing. She's the math teacher I wish I'd been lucky enough to have when I was in middle school. She's organized, demanding, witty, and kind, and every time I poke my head into her classroom, her students are enjoying themselves.

I know! That was a new concept for me, too.

I checked the middle school schedule and realized I have a prep period during her Algebra I classes on Wednesday and Friday, so starting next week, I'm back in school. I will have my own textbook, and I will even try to do some of the homework once I catch up to the kids (if that even happens).

It's time to put my money - well, my pride, I suppose - where my mouth is. I encourage my students to be brave, diligent, and never back down from an intellectual challenge. I try to model a love of education, a genuine thirst for knowledge that drives what I read, watch, and listen to. They know I am a frequent buyer at The Teaching Company, and that I listen to lectures on my iPod when I stack wood, fold laundry, and chop vegetables for dinner. Currently, I'm listening to a course on the evolution of the English language, and I love to share the tidbits I've gleaned with my students. They know I listen to courses on English, history, and science, but they also know about my math aversion. They joke about it. I joke about it. But it's not really that funny; it's actually quite sad.

I am hoping that my efforts to remedy my math anxiety will put weight behind my words. I hate math, yes. I hate the obsessive attention to plusses and minuses. I hate the inflexibility of numbers. But the excuse that "my brain just does not work that way" doesn't cut it when I simultaneously tell my students that they can do anything - anything - they want to do.

Well, dammit, so can I.

Friday, March 9, 2012

Exponent Negativity


An 8th grade student approached me yesterday after third period. I had just taught composition class - the composition class that conflicts with the Algebra I class I have been attending in order to get over my math anxiety.

"Mrs. Lahey, I we did some hard stuff in math today, and we were really worried that you'd get behind, so I agreed to take notes for you and teach you the lesson. I can come by during lunch today and explain what we learned, if you want."

This reversal just slays me. My students are worried for me. Worried about my ability to keep up in math class. How sweet is that? I was really touched. One of the things I love most about my school is the sense of community, but until yesterday, this community had always been a "them" and "us" community. We adore our students, mind you, but as much as we'd like for our community to be one, big, fuzzy "us," it's not. Students are students and teachers are teachers, and never the twain shall meet.

Until yesterday.

Before I start getting attacks from readers who think I am trying to create inappropriate relationships with my students - relationships I am supposed to view as rigidly hierarchical and hopelessly lopsided as a power structure - know that I am not trying to be my students' friend. I just think it's good for them to see adults not know things, and not be afraid to not know, and not run from not knowing.

I talk and talk about the importance of viewing education as a lifelong process rather than a means to some calligraphy-on-parchment end, and my attempt to work through my math anxiety is proof of statement. I really mean it. I love to learn - and not just the stuff that comes more easily. Even the stuff that makes me want to give up and run screaming in the other direction.

Stuff like this:


As I am a newly minted Algebra I student, let me break this explanation down for you.

[Silence, eventually the sound of fingers tapping idly on the keyboard, as I attempt to think of words appropriate to the material contained in the scanned image, above.]

Okay. Here's what I know. I must accept the fact that any number to the power of zero = 1. Ellie, my English-student-cum-Algebra-mentor explains that concept in her red notes above. I don't understand it, but I accept that it's a rule, and follow it.

The other thing I learned is this: if an integer is negative, you can stick it at the bottom of a fraction under a one, and it magically becomes positive. I don't know why, but if I simply accept this and apply it, my homework answers are right. I got through a difficult problem set today through the blind application of these two rules.

I'm not proud of this reality; I'm just owning it. I just don't get it. Alison Gorman, my colleague, friend, and math teacher is patient and kind and generous with her time, and I feel as if I get it for a second or two after she explains it to me, but then, poof, it's gone.

This has always been my problem with math. I try to understand the whys and wherefores of the rules, I really do, but the why just goes over my head. I don't know if it's because I don't care, or because I know that in the end, if I just decide to accept the rule and use it, I can get by through sheer grit and application of the rules I don't really understand. That's how I got through high school math.

Alison is one of the most effective, organized, creative, and dedicated teacher I have ever met, and yet, I think she may have met her match in me. She's extremely patient, and more than a little entertained by my efforts, but I'm afraid she's going to realize that I have severe limitations where numbers are concerned.

I will continue to try to understand, because I hate that I don't. I hate not knowing. I hate butting up against my limitations.

It's time to bust through the negative and transform those integers into their positive form once and for all.


Monday: Powers of 10 and Scientific Notation.

Part V of my math odyssey can be found here.

Wednesday, March 7, 2012

Exponents, Products and [my mathematical] Powers




"Everyone who beats Mrs. Lahey on this problem set will earn extra credit points."

Oh, dear. Extra credit points will be flowing like New Hampshire spring runoff thanks to Mrs. Gorman's misplaced faith in me.

When I decided to return to Algebra I in order to get over my math anxiety, I knew I'd have some catching up to do. I stumbled into class on the last day before a unit test, in the last week of the second trimester. I paid little attention in Algebra I the first time around, and that was 30 years ago.

Helpful hint: If you plan to return to Algebra I in middle age, start on the first day of a unit, not the last.

I did my best to catch up with the kids, and Alison Gorman is the best math teacher I've ever seen, but if you glance back up at the scan of my first practice set, you can see how badly I tanked. The red "C" in the middle of the sheet was the one problem I got right on the first try. I had totally forgotten what to do with exponents, could not remember what the distributive property was let alone how to use it, and my hand cramped up about four pages into my notes.

That one correct problem turned out to be my only correct problem. But it reveals I learned at least one new thing yesterday, and that's good, right?

The students loved it. My students taught me. One taught me about domain and range, another explained why you add exponents when the bases are multiplied, another whispered the number of the problem we were supposed to be working on when I missed Alison's instructions. Hey, come on, I was taking notes. It's hard to listen to write and listen at the same time. I will try to remember that next time I start talking when my students are still writing.

I can't attend Alison's class every day because my teaching schedule overlaps with some of her math classes, so a fair amount of confusion is to be expected. But that first day was just silly.

Today was better, though. The class started a new unit, "Exponents, Products, and Powers," so I stood a fighting chance. We were all on the same starting line, give or take thirty years. As we moved through the exercises, I started to see it. I have my list of properties - power of a product, product of a power with equal bases, power of a power, power of a quotient...and on and on - and I have to refer back to them, but they are slowly sinking in.

I got some insight into my basic issue with math when I proudly told my son Ben about my day. We have a tradition at dinner - "high, low, funny." The best thing in our day, the worst, and the funniest. My best and my funny were both math class, but Ben provided the worst. I recounted the properties I'd learned, and told him how proud I was of myself for remembering that when you multiply variables raised to a power, you simply add the exponents. Ben looked at me like I was an idiot and said,

"Well, that just makes sense. Of course you add the exponents."

And there you have it, ladies and gentlemen, the difference between my brain and the brain of someone who naturally gets math. I can't see it. I can repeat the steps if someone shows them to me, I can replicate the process, but I don't think any of my teachers spent much time explaining the "why" of the process to me.

For example, we did this problem today:


Look at the one without all the scribbles and crosses through it. I have no problem leaving the exponents well enough alone when they are next to an X or a Y, but put them next to a number, and they call out to me. The 12-year-old in me has to DO something with them. Create something. Find an answer, multiply all those threes, no matter what. That's the part under the big cross-out. I made mistakes because I solved for all sorts of unnecessarily large numbers. 

Must. Multiply.

But today, the grown-up, rational teacher in me had a breakthrough. If Alison, teacher extraordinaire, hands her students a problem where the exponent is higher than 3 or 4, and she's not letting them use their calculators, and she's not particularly in the mood to torture them, she probably does not mean for them to do the multiplication. She's probably hinting that there's a simpler method. 

So, two things. I learned two things today. 

But now I have to head out to the dining room table. I have a lot of homework and a teenage son to impress.

Part IV of my math odyssey can be found here