The main purpose of this study was to test the effects of word-problem (WP) intervention, with versus without embedded language comprehension (LC) instruction, on at-risk 1st graders' WP performance. We also isolated the need for a structured approach to WP intervention and tested the efficacy of schema-based instruction at 1st grade. Children (n ϭ 391; M age ϭ 6.53, SD ϭ 0.32) were randomly assigned to 4 conditions: schema-based WP intervention with embedded language instruction, the same WP intervention but without LC instruction, structured number knowledge (NK) intervention without a structured WP component, and a control group. Each intervention included 45 sessions, each 30 min long. Multilevel models, accounting for classroom and school effects, revealed the efficacy of schemabased WP intervention at 1st grade, with both WP conditions outperforming the NK condition and the control group. Yet, WP performance was significantly stronger for the schema-based condition with embedded LC instruction compared to the schema-based condition without LC instruction. NK intervention conveyed no WP advantage over the control group, even though all 3 intervention conditions outperformed the control group on arithmetic. Results demonstrate the importance of a structured approach to WP intervention, the efficacy of schema-based instruction at 1st grade, and the added value of LC instruction within WP intervention. Results also provide causal evidence on the role of LC in WP solving.
Educational Impact and Implications StatementThis study yields three conclusions about effective word-problem (WP) intervention for at-risk first graders. The first conclusion is that arithmetic intervention does not improve WP performance; instead, structured WP intervention is required. Second, structured schema-based WP intervention, which teaches children to understand WPs in terms of problem types and to align problem-solving strategies with the problem type, improves WP performance. Third, schema-based WP intervention is more effective when it embeds WP language instruction that teaches children the importance of understanding language in the context of the complete WP (not as key words).