Think Out Loud

Taking implicit racial bias out of K-12 mathematics education

By Allison Frost (OPB)
June 14, 2021 9:07 p.m.

Broadcast: Tuesday, June 15

Students at Abernethy Elementary who opted out of standardized tests were given other work to do. In this 5th grade classroom, they're doing math worksheets.

In this 2020 file photo, a students at Abernethy Elementary works on math exercises.

Rob Manning


Teachers’ unconscious racial bias in the classroom can significantly affect how different students are taught — and what they learn. Portland State University Math Education professor Eva Thanheiser has just won a $640,000 grant to preemptively reduce bias among K-12 math teachers. The effort does not develop a curriculum. Instead, it takes a professional development approach for teachers to bring in the experience of students from all racial backgrounds into what and how they’re teaching. We learn more from Thanheiser about how she uses this basic approach in her college classes and the broader effort to excite and engage all students in math and boost their achievement.

This transcript was created by a computer and edited by a volunteer.

Dave Miller:  From the Gert Boyle studio at OPB this is Think Out Loud. I’m Dave Miller. Eva Thanheiser wants to improve math education in this country. For her that doesn’t just mean teaching kids to do arithmetic and quadratic equations. It’s about helping all kids in a math classroom to thrive and getting them to understand the ways that math is connected to their lives. Thanheiser is Professor of Mathematics Education at Portland State University. She’s a member of two different research teams that won recent grants from the National Science Foundation. One grant will fund work on anti bias math teacher education. The other is focused on getting teachers to connect math concepts to real world applications. Eva Tannhauser, welcome to Think Out Loud.

Eva Thannheiser:  Thank you for having me.

Miller:   Let’s start with the anti bias grant and the most basic question.  What’s the problem that you’re trying to solve?

Thannheiser:  What’s happening in classrooms sometimes is not quite visible. Our earlier work [included] teachers in classrooms. We were working on helping all students justify and generalize in the math classroom and engage in authentic math activities. Professional development was really working well and we got a National Science Foundation grant to study it. We found that teachers learned and we found that the students all did better.

But then when we disaggregated our data, what we found was pretty shocking. While the white students and the majority students did better, this was not true for Black and Hispanic students. They actually ended up doing a little bit worse. And so we realized [that]teaching all students or giving all students access isn’t the same as giving Black students access or giving Hispanic students access.

So we want to dig back into this professional development and look at what we need to do to allow Black students to thrive in this environment as well and not be hidden in the statistics that indicated we were doing well. It wasn’t until you dug into the actual composition of particular classes that you saw that Black and Hispanic students were not just not doing better, but were doing worse in some cases.

Miller:  Do you have a sense for what was actually happening in those classrooms that led to those outcomes?

Thannheiser:  That’s actually what our grant is about. If we think about biases, there are two things all of us have to deal with - implicit bias, the unconscious way of how we interact with people. It happens to teachers, even if they intend to, for example, call on girls the same amount as they call on boys.  They call more on boys. We grow up in this country [with] judgments and these expectations that might not be fairly distributing access to everybody.

There’s also the larger structural issues that Black students are overrepresented in special education and disciplinary actions and underrepresented in advanced math classes and high test scores.  Those kinds of things all played together.


Miller:  You know, it’s interesting that you noted that even when teachers are consciously trying to interrupt their own behavior to make sure they’re not calling less on girls than on boys. They still may call on boys more. It’s a good example of the difficulty here if you’re trying to deal with your own implicit bias, even consciously. So what kinds of systems can be put in place to counteract something that we do, unthinkingly?

Thannheiser:  There are multiple things. First of all, becoming aware of doing this is step number one. There are tools [ can measure who teachers call on and how students participate. For example, are certain students only giving 12 or 3-word answers versus other students [who]are giving longer answers. How does classroom participation distribute? Measuring that is step one. Hav[e] teachers become aware and measure that on their own.

And then there’s ways that we can work with teachers to allow more opportunity. This includes changing [some] of the context and changing [some] of how we allow students to participate. So our grant aims to learn from the students in the classroom. What kind of participation would help them become more active members? What are the kinds of contexts that they might be interested in exploring that would get them excited?

Miller:  About a month ago, we talked to a reporter who was covering the Bend-La Pine School Board elections and he told us about one of the candidates who was complaining about critical race theory and complaining about [as] he described it, ‘Math was going to be watered down or made into non math to appease progressives’. Essentially he was saying that kids are going to be told that even if two plus two is four, if you say two plus two is five, that’s fine. That was his caricatured version of the way the teaching of math is changing because of progressive values. I’d love to get your take as a math educator teacher on [whether] there’s any truth to his criticism.

Thannheiser:  So thank you for asking this question. I would say if we look at it context free, two plus two is four.   Nobody would say two plus two is five. However, I think the argument is [that] context actually matters. For example if you say ‘two terriers and two german shepherds are not four german shepherds though they are four dogs, right? So the question of [whether]  2+2  is always 4 is a matter of context. It is 4 of something, but it is not always four. I would like to turn this argument around [to]be a way of understanding the world.  Then maybe [math] wouldn’t be such a boring thing that we don’t make sense of.  So we change teaching where we still teach math but in context.

For example, one [classroom] task is called ‘if the world were a village’. [We] shrink the world population down to a village of 100 people and then examine [how] the world looks. In this village of 100 people, every person represents about 78 million people, because we shrink it down to be representative. And then I ask ‘how many of these 100 people come from the United States and how many of these 100 people speak english?’ Then we talk about it and after they predict, we look at it and say, ‘4 of the 100 people come from the United States’. Every single one of my students over predicts this and the same with speaking english.  Students think most people speak english but now that we have this 100 person village, we can understand that per cent means per 100. So how many per 100 come from the United States? 4 per each 100, now understanding what percent means. Many of my students at college have never put together that percent actually has a meaning of per 100. So instead of just teaching how to find the percent number, it [is] in context and something about the world [is understood while] learning the mathematics.

Miller:  That second National Science Foundation grant aimed at helping teachers make math more “meaningful, relevant and applicable, both inside and outside the classroom”. It almost seems like this grant was designed as a way to help teachers better respond to ‘when am I going to need this?’ Is [it] fair [to say] you want to equip teachers to either answer that question or make it so their students know the answer and don’t even feel the need to ask it?

Thannheiser:  We want to teach math in a meaningful way. [It] should be a way to make sense of the world and then potentially a tool to change the world. So [the 2 NSF grants] are interrelated every day. For example, the Supreme Court if people [are added], how does that number [affect] the power of each person on the Supreme Court? How much voting power do they have? There’s ratios and proportions.

We can link math to making sense of the world. And with that we answer the question, ‘why do I need to know this’? I need to know this because [it] helps me understand what’s going on and then hopefully gives me the power to address some of the inequities that I’m also learning to make sense about.

Miller:  I can’t help but think that both of these grants are what I want teachers to have been doing anyway. A good teacher would figure out ways to reach all students to make them care about, maybe even love a subject, but at the very least understand why it’s important. Is it fair to say the necessity for these two grants [results from] a sign that something has really gone wrong?

Thannheiser:  Yes and no. I think the intent of most teachers is to make things relevant and help students connect. However, if you look at the issues, teachers are overworked and the whole implicit [bias] thing. I myself walked in there [believing] it works for all students. And so I think we need to really go beyond that. Good intentions aren’t enough.  Also there are just no resources. So yes it is a failure in a sense that we don’t have curricula available for teachers to just go ahead and teach this way. But we’re trying to address that.

Miller:  Why did you want to become a math teacher? Why did you want to become a teacher of math teachers?

Thannheiser:  As a kid I struggled in school to the point where like they didn’t even think I would finish high school.  But in math I was always solid and just loved it and kids and I think this combination is why I wanted to be a teacher.  I grew up in Germany and I studied to be a teacher and I had to do math and then I had a second subject which was english. I came to the US and discovered that mass education is a field.  I was like oh my god this is what I want to do. [While] learning about teaching teachers I was just fascinated with the real struggles that adults had in making sense of mathematics and I love working with teachers. So here I am.

Miller:  Eva Thannheiser, thanks very much for joining us. Eva Thannheiser is a Portland State University Professor of Mathematics Education.

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