I should preface this by saying that I have a pretty major bias in favor of Jo Boaler's work. This is not for reasons of blind faith, but because of how I have been "raised" as a math teacher. The teaching methods I've learned and successfully used have been the study of her research, not to mention that most of my math teaching heroes were either her research subjects or worked/studied with her at Stanford.
But regardless of all my biases, Dr. Boaler always has interesting things to say. Her doctoral thesis was a study of two schools in England, one using traditional mathematical teaching methods and one using "reform" methods. The differences between the two schools were startling. The students at Phoenix Park (the reform school) had much better conceptual understanding as well as a more positive and productive attitude towards math than the students at Amber Hill (the traditional school). There's more in her thesis if you want details. The same study was repeated at similar schools in the United States. The results were published in the Phi Beta Kappan under the title "When Leaning No Longer Matters," if you're interested. And you should be interested.
A couple years ago Boaler was giving a talk about her England study and a man in the audience asked if she knew what had happened to those students. It turned out that he happened to be a rich oil tycoon who was willing to fund her to go back and find out. So she did, and presented the results at Asilomar. Again, the results were fascinating. Part of her general thesis is that math classes literally traumatize and leave life-long scars on students. All math teachers know this anecdotally from the reactions we get upon telling people our profession. "Oh, I hated my high school math classes." "Wow, you're brave! That was my worst subject." "I actually like math" (as if that should come as a surprise).
So how would adults feel about math if they came from a reform background? The Phoenix Park students (now in their mid- to late-20's) definitely had a more positive attitude toward math, both as a general interest and in how they used it in their jobs. Dr. Boaler asked both groups what they do when they come across a math problem they can't solve. Most Amber Hill (traditional) students said something to the effect of, "I would ask someone who's good at math." One Phoenix Park student responded, "Why wouldn't I be able to solve it? If I didn't get it I would just keep working until I did." As a math teacher, that warms my heart. Even my "smartest" kids struggle with persistence more than pretty much everything else. I definitely believe (and lots of research has shown) that persistence and belief that you are capable of succeeding in a math problem are key factors in how well people do on tests.
For those who don't care about the wishy-washy how do people feel about math, Dr. Boaler had some pretty stark numbers. Both groups of students she interviewed were coming from similar socioeconomic backgrounds. For the Amber Hill students, their range as adults got wider, meaning that some did move up to higher levels, but just as many fell. The range of the Phoenix Park students stayed the same width, but moved up, meaning that very few, if any, students ended up at a lower socioeconomic class than their parents. That in itself is impressive and also has serious implications for raising low-income communities out of poverty.
In the age of high-stakes testing (I know this is how so many sentences in education writing start off...), there is so much pressure to teach to the test, to jam facts into kids' heads so they'll remember them for 2 hours in April. It's so tempting to teach them stupid tricks and drill them to memorize formulas without any reasoning behind it. It's definitely easier to write a worksheet of 100 drill-and-kill problems than it is to come up with one good groupworthy one. But Dr. Boaler's talk was definitely the reminder I needed that teaching conceptually, getting kids to talk about math, and helping them value different ways of seeing are such worthwhile goals. It's hard when my standardized test results don't seem to demonstrate how smart I think my students really are, but if they can go into their adult lives believing that they are capable of math and having the habits of mind to think mathematically, I'm a little less worried about their CST scores.