Common Core Standards
Grade 4
Language L.4.6
Acquire and accurately use grade-appropriate general academic and domain-specific words and phrases, including those that signal precise actions, emotions, or states of being (e.g., quizzed, whined, stammered) and that are basic to a particular topic (e.g., wildlife, conservation, and endangered when discussing animal preservation).
The main goal of these standards is to ensure that your students understand the language of a given topic. We don't want them talking about "kitties" when they're doing a report on tigers. We want them speaking in an appropriate manner that demonstrates their knowledge acquisition. Part of that demonstration is using suitable words and language for a topic. Give them the vocab sheets. Hand them the knowledge. Watch them flourish.