Science Vocabulary and Science Achievement of Children With Language/Literacy Disorders and Typical Language Development

Purpose: This study examined science achievement; science vocabulary knowledge; and the relationship between science vocabulary, language skills, and science achievement in school-age children with language/literacy disorders (LLDs) and typical language development (TD). Method: Thirty-nine sixth graders (11 with LLDs) completed standardized assessments and researcher-designed science vocabulary measures over Zoom. Scores for the AIMS Science, a standardized science assessment administered to all fourth-grade public-school students in Arizona, served as the outcome measure for science achievement. Linear regression analyses were performed to examine the relationships among science achievement, general language skills, and science vocabulary knowledge. Group comparisons (TD vs. LLD) were also completed for science achievement and science vocabulary measures. Results: General language skills, science vocabulary breadth, and science vocabulary definition scores uniquely predicted science achievement, as measured by AIMS Science scores. General language skills predicted performance on the science vocabulary breadth and definition tasks. Participants with LLDs scored significantly lower on science achievement and vocabulary measures relative to their peers with TD. Conclusions: Students with LLDs demonstrated poorer science achievement outcomes and more limited knowledge of science vocabulary breadth and semantic depth. Greater science vocabulary knowledge was associated with higher science test scores for children with LLDs and TD. These findings indicate that increasing science vocabulary knowledge may improve science achievement outcomes for students with LLDs or TD.