Your words count

You’re just not good at math

That book is beyond your reading level

College isn’t necessarily for you

Why do teachers insist on making disparaging comments that pigeonhole students?

These comments are all ones my own students and grad school classmates have heard from other teachers — probably well-intentioned teachers who thought they were giving sound, honest advice.

But the students all felt undermined and insulted. In the case of the math comment, the young woman disengaged and gave up on learning math at all.

Why would she give that one teacher so much power over her life? Because kids do. When a voice of authority speaks, no matter how much kids act like they ignore it, they listen and internalize it.

I don’t think teachers realize how powerful their offhand comments can be. We need to acknowledge this power and use it for good.

Carol Dweck, author of Mindset, has studied extensively how damaging it is to communicate a fixed mindset to children. Much of her work has focused on how praise that communicates a fixed level of intelligence — even as a compliment — can limit children’s effort.

Comments that communicate a fixed, negative condition are even worse. When a teacher tells a child that he is not capable or competent, he will take it to heart. It can shape his entire life.

But comments that encourage and empower children to make an effort and take on a new challenge can be equally powerful.

When I think about how words influence us, I always think back to Mr. Biddinger, my 7th grade math teacher.

Honestly, I don’t remember much of what I learned in junior high, let alone in that class. I remember wishing I was more popular, better looking and better at sports, and school was mostly an afterthought.

But I remember what Mr. Biddinger said to me.

In addition to teaching math, Steve Biddinger was the girls volleyball coach, and that was the only sports team I ever made. I wasn’t gifted at volleyball, but I was tall, so he gave me a chance. I barely ever played.

In spring of 7th grade, my school, McClure Junior High, decided it would offer Algebra to 8th graders for the first time the following year. At the end of class one day, Mr. Biddinger pulled me aside and told me that I was doing really well in math, and that I should take Algebra.

I was resistant and embarrassed — I didn’t want to be some nerdy girl — but I saw the opportunity to make a deal. I told Mr. Biddinger, who was young with a thick ’70s mustache and a great tolerance for stupid teenage behavior, that if he would let me start in the next volleyball game, I would tell my parents to put me in Algebra.

He did it, and so did I. I didn’t do much in that game, but I went on to become a stellar math student, and I even got a math scholarship when I went to the University of Michigan.

Mr. Biddinger told me I could do Algebra, and I believed him. In the late ’70s, coming out of an era when girls had always been told that “math was for boys,” that was a pretty big deal. The fact that he was willing to bribe me? Priceless.

It’s so easy to categorize and stereotype students in our minds. That student is good at writing; this one is pretty weak; that one should work with his hands. We are so sure that we know their abilities and even their destinies. But if you knew that a child would carry your message with them for the rest of their lives, what would you really want to say?

Next time you’re ready to tell a student they aren’t good at something, my advice is: Stop talking. Think about how you can encourage this young person’s effort, or don’t say anything at all.