The current intervention tested whether a metacognitive self-regulatory strategy of goal pursuit can help economically disadvantaged children convert positive thoughts and images about their future into effective action. Mental contrasting with implementation intentions (MCII) entails mental contrasting a desired future with relevant obstacles of reality and forming implementation intentions (if–then plans) specifying when and where to overcome those obstacles. Seventy-seven 5th graders from an urban middle school were randomly assigned to learn either MCII or a Positive Thinking control strategy. Compared to children in the control condition, children taught how to apply MCII to their academic wishes and concerns significantly improved their report card grades (η2 = .07), attendance (η2 = .05), and conduct (η2 = .07). These findings suggest that MCII holds considerable promise for helping disadvantaged middle school children improve their academic performance.