Glaring truism alert!  Subject-specific vocabulary is extremely important. The right academic vocabulary turns a clumsy conversation into an elegant and precise one.

In mathematics we have the issue that certain words have a different meaning in common speech, take “roots” or “degree” for instance (degree has more than one meaning even in mathematics – the degree of a polynomial, degrees in a turn). We also have words that it is perfectly plausible to leave out of the curriculum, and that you will find many students never encounter (such as “commutative” or “subtrahend”). But how much better is it if teacher and student have a shared technical vocabulary, one which helps us to be mutually understood and to express ourselves unambiguously.

It can be tempting to avoid complex words with students, especially those who aren’t the highest-attaining, yet I’d argue that, in the pursuit of increasing attainment, all our students benefit when they can express themselves clearly and succinctly.

During lessons I reserve the rightmost side of my whiteboard for my Key Words column, where I write the mathematical vocabulary as we come to it. The students write it in their books, and whenever someone answers a question or explains their thinking in way which could be improved with one of the key words my response would be along the lines of, “you’re absolutely right, now how can you say that using the right word(s) from the list?” If they’re not sure, I ask someone else to help. By modelling the use of vocabulary and requiring students to say it themselves whenever possible I believe they are more likely to remember it.
It is also important, on the principle of spacing, to revisit previous technical words when you can to improve their retention. Before Christmas I was doing prime factor decomposition with year 7 and someone asked whether  the answer of 30 = 2 x 3 x 5 could be written in a different order. I opened it up to the class and someone said that it didn’t matter “because you can multiply numbers in any order and get the same answer”. I could leave it at that, but there is a better way to answer the question, so I asked the class, “and what do we call this property of multiplication?”  Some could remember the word commutativity“, but not all. Now they’ve been reminded though, so they are less likely to forget again, and next time the opportunity arises we will remind ourselves of the word, until it becomes their first answer.

All of the key vocabulary is in our knowledge organisers (which I am still working on but will share at some point) and I regularly get students to refer to these.  As an extra touch, we rotate difficult words as our passwords for programs, so the students are forced to learn their spellings (by hook or by crook!)

I have noticed a big difference in the ability of my students to explain their thinking and to understand what they read since doing this habitually and it extremely easy to implement in a classroom – good ideas often are.

N.B. If you have never read Teach Like a Champion by Doug Lemov please do so. The rationale behind increasing our focus on vocabulary like this came from the book, which is the best teaching manual I have read in more than a decade.