Purpose: Language serves as an essential resource to learn about cause and effect throughout childhood. Causal adverbial sentences use causal conjunctions (e.g., because, so) to join 2 clauses to express cause-effect relationships (Diessel & Hetterle, 2011). Causal adverbial sentences are frequently used to explain causal relationships in academic contexts, such as elementary school science and social studies classes (Kinzie et al., 2014; J. Williams et al., 2014). Children with developmental language disorder (DLD) are at risk for failure in these academically relevant language skills. Here, we investigated the effect of language intervention focused on causal adverbials on both causal adverbials and acquisition of science content in young children with DLD. Method: A multiple-probe design was used to examine the effect of language intervention using recasts on production of causal adverbials and acquisition of science content for 7 preschool/kindergarten children with DLD. Child production of causal adverbials and an untreated control structure were analyzed. Results: Six of 7 participants exhibited gains in production of causal adverbials containing because, with effect sizes ranging from small to large. Performances on daily probes of science content learning and science unit tests indicate that participants are able to learn science content, but the magnitude of gains may not relate to skill in causal adverbial production. Conclusion: Language intervention for young children with DLD can effectively treat complex syntactic targets such as causal adverbials in the context of science instruction, but it is unclear whether this can affect science content learning.