The purpose of the two studies reported in this article was to examine technical features of curriculum-based measures for beginning writers. In Study 1, 50 first graders responded to word copying, sentence copying, and story prompts. In Study 2, 50 additional first graders responded to letter, picture-word, picture-theme, and photo prompts. In both studies, 3- to 5-minute prompts were administered in winter and spring and scored using a variety of quantitative procedures. Students were also administered the "Test of Written Language--Third Edition", and teacher ratings and scores on a district rubric for writing were collected. Test-retest (Study 1 only) and alternate-form reliability, criterion validity, and winter-to-spring growth were examined for each measure. Sentence-copying, story, picture-word, and photo prompts emerged as promising beginning-writing measures. Findings have implications for monitoring student progress within a seamless and flexible system across ages and skill levels. (Contains 5 tables and 5 figures.)