When students read more, vocabulary knowledge increases (Cunningham & Stanovich, 2003; Krashen, 2004). Out of every 100 unknown words that students encounter while reading, they learn an average of 15 of them from text alone (Swanborn & de Glopper, 1999). In addition, as students age, they are more likely to infer word meanings, indicating…

This article describes the importance of vocabulary knowledge in adolescents' reading comprehension, particularly for students with disabilities. Students with stronger vocabularies tend to have better background knowledge and improved understanding of content-area texts. We describe evidence-based vocabulary instructional practices that…