"The limits of my language mean the limits of my world." Ludvig Wittgenstein
A rich vocabulary is necessary for, and facilitative of academic success. It plays a key role in oral comprehension, reading comprehension and written languauge.
In high school, vocabulary is increasingly specialised, decontextualised and encountered less frequently. This means that it is unlikely that students will learn all the vocabulary they need from reading alone. Vocabulary instruction is, therefore, necessary.
As teachers, we can positively impact our learners' vocabularies. We can't teach all the words there are, but we can teach the Tier II academic instrucdtional words and Tier III subject discpline vocabulary that are critical for learner success. Instruction that provides memorable encounters with key words, opportunities to review and retrieve is most effective.
It is important that we construct topic word lists/lists of words that need our learners to know and that we directly teach and review them. These lists also provide powerful communication home. See the Rutherford College Tier 2 Academic Word List