Talk nerdy to me: Teachers who use math vocabulary help students do better in math

Students, parents and school principals all instinctively know that some teachers are better than others. Education researchers have spent decades trying — with mixed success — to calculate exactly how much better.

What remains far more elusive is why.

A new study suggests that one surprisingly simple difference between stronger and weaker math teachers may be how often they use mathematical vocabulary, words such as “factors,” “denominators” and “multiples,” in class.

Teachers who used more math vocabulary had students who scored higher on math tests, according to a team of data scientists and education researchers from Harvard University, Stanford University and the University of Maryland. The size of the test score boost was substantial. It amounted to about half of the benefit researchers typically attribute to having a highly effective teacher, which is among the most important school-based factors that help children learn. Students with highly effective teachers can end up months ahead of their peers. 

“If you’re looking for a good math teacher, you’re probably looking for somebody who’s exposing their students to more mathematical vocabulary,” said Harvard data scientist Zachary Himmelsbach, lead author of the study, which was published online in November 2025.

The finding aligns with a growing body of research suggesting that language plays a critical role in math learning. A 2021 meta-analysis of 40 studies found that students with stronger math vocabularies tend to perform better in math, particularly on multi-step, complex problems. Understanding what a “radius” is, for example, can make it more efficient to talk about perimeter and area and understand geometric concepts. Some math curricula explicitly teach vocabulary and include glossaries to reinforce these terms.