Say What You Mean: The Power of Math Vocabulary

Recently, our middle school teachers participated in OGAP training, and one theme echoed across every content strand: mathematics is a language. Like any language, understanding depends on consistent and meaningful vocabulary — not just introducing terms, but intentionally maintaining them across lessons, units, and grade levels.

A perfect example appears when students learn to divide fractions. In middle school, we carefully teach students that dividing by a fraction means multiplying by the reciprocal of the divisor. But somewhere along the way, this rich understanding can shrink into the phrase “keep, change, flip.”

While catchy, the phrase quietly removes the mathematics:

What are we keeping?

What is changing?

What exactly are we flipping?

More importantly, students lose powerful words like reciprocal and divisor — words that reappear later in algebra, geometry, and standardized assessments.

During the recent ACT teacher bootcamp at James Clemens High School, this idea surfaced again. Teachers were reminded that assessments rarely use terms like “flip it and change the sign.” Instead, students encounter precise mathematical language, such as negative reciprocal, when determining perpendicular slopes. And suddenly — there’s that word again: reciprocal.

Following these professional learning experiences, teachers have begun intentionally strengthening vocabulary through:

• Word walls that grow with each unit

• Matching and vocabulary sort activities

• Intentional use of academic language in questioning and assessment

• Students explaining processes using precise terminology

These small shifts help students move from doing math to thinking and communicating mathematically. Because in the end, math isn’t just about getting the right answer — it’s about understanding why the answer makes sense and having the language to explain it.