The present article includes 2 studies that were designed to expand the literature on the technical features of vocabulary matching. The purpose of both studies was to extend validity research on the general outcome measure of content knowledge. In Study 1, direct comparisons of predictor-criterion correlations related to selected standardized and curriculum-based instruments were made with a diverse sample of 153 sixth-grade students from 3 middle schools. Among other findings, direct correlation comparisons indicated that the relation between vocabulary matching and the state accountability test was statistically significantly stronger than those between other curriculum-based measures. In Study 2, linear mixed modeling was used to compare growth rates for a sample of 224 sixth-graders from the same 3 schools. Participants were administered 25 weekly probes over the course of a school year. Findings demonstrated growth rates that were significantly different from a zero growth hypothesis and variable across learners and probe type. Research implications for vocabulary matching are discussed.