Which type of vocabulary includes common words that children already know when they enter school?

Tier 1 vocabulary refers to the most basic, everyday words that children typically learn through everyday conversations and experiences before they enter school. These words are fundamental and often reflect concrete objects, actions, or concepts familiar to young children, such as "dog," "run," or "happy." This type of vocabulary is crucial because it forms the foundation of language development and comprehension skills.

Understanding Tier 1 vocabulary is essential for educators when designing effective literacy instruction. By building on the words that children already know, teachers can help young learners expand their language skills and develop greater fluency when they encounter new words or more complex language structures. In contrast, Tier 2 vocabulary consists of high-frequency words that are more abstract and found in texts across different subjects, while Tier 3 vocabulary encompasses subject-specific or technical terms that are typically taught in content-area instruction. Academic vocabulary is closely related to Tier 2 but may not align strictly with the developmental levels of early learners.