We investigated the criterion-related validity of four indicators of curriculum-based measurement in writing (WCBM) when using expository versus narrative writing prompts as compared to the validity of passage copying speed. Specifically, we compared criterion-related validity of production-dependent (total words written, correct word sequences), accurate-production (correct minus incorrect word sequences [CIWS]), and production-independent (percent of correct word sequences [% CWS]) scoring methods on narrative and expository writing probes in relation to a state-mandated writing assessment. Participants included all tenth grade students (N = 163) from a rural high school in the Midwest. Results indicated that the more complex indicators of writing, % CWS (when taking into account passage copying speed), and CIWS (when passage copying speed was not considered) on narrative probes explained the greatest amount of variance in the criterion measure. None of the WCBM indicators, alone or in combination with passage copying speed, explained more than 25% of the variance in the state writing assessment, suggesting that WCBM may have limitations as a universal screening measure for high school students. (Contains 2 tables.)