This study examined whether curriculum-based measures (CBMs) of math word-problem contributed unique variance in predictions of performance on high-stakes tests, beyond the contribution of calculation and reading skills. CBMs were administered to a representative sample of 142 third-grade students at three time points. Results indicate that problem-solving CBMs uniquely predicted a problem-solving composite measure and the "California Standardized and Reporting" test, and were able to discriminate students at risk and not at risk for math difficulties. Implications for practice are discussed.