When teaching vocabulary, what should not become the sole focus, according to educational best practices?

Focusing solely on Tier III words is not aligned with educational best practices for teaching vocabulary. Tier III words are highly specialized and relevant to specific disciplines; they include technical terms and are typically used in academic contexts. While it’s important for students to acquire some knowledge of these terms, especially as they advance in their education, an overemphasis on them can limit students' overall vocabulary development.

In contrast, Tier II words encompass a broader range of vocabulary that students will encounter across various texts and subjects. These are high-frequency words that provide rich meaning and can enhance comprehension. Teaching these words is essential as they appear frequently in literature and academic subjects, thus supporting students' access to a wide array of content.

Contextual understanding is also crucial in vocabulary instruction. Learning words in context helps students grasp their meanings better and apply them appropriately. Basic vocabulary is foundational and essential in early education. A well-rounded vocabulary program should ensure that students are exposed to a range of word tiers to cultivate a robust vocabulary and improve their reading and comprehension skills. Hence, balancing instruction across all tiers, rather than focusing exclusively on Tier III words, is vital for a comprehensive vocabulary development strategy.