The purpose of this study was to examine the extent to which commonly used core reading curricular materials supported research-based pedagogical features for oral vocabulary instruction in kindergarten. A document analysis was completed for 12 weeks of instructional materials from the teacher's editions of the 4 most widely used curricula. Results indicated disparities across curricula in the number of words addressed, ranging from 2 to 20 words identified for instruction per week. Organizing principles for word selection were unclear for 3 of the 4 curricula, and many target vocabulary words were rated as too easy or basic for school-based instruction. Programs differed greatly in the frequency of instructional practices provided to support teachers and in their application of an instructional regime. These results suggest that instruction in kindergarten core curricula does not reflect the current research base for vocabulary development and may not be systematic enough to influence children's vocabulary learning trajectories. (author abstract)