A formative intervention was employed to expose children to a variety of words to increase the breadth, or size of their vocabularies, and to repeatedly and supportively expose children to words to increase the depth, or semantic understanding of vocabulary. Science content words were selected since they are less likely to be included in an average young child's everyday vocabulary. Early, effective science vocabulary instruction to introduce both science social language and general academic language may help children build a strong conceptual and linguistic foundation for later instruction. The pedagogical goal was to design a simple, yet effective intervention that could be easily implemented in the participating kindergarten classrooms to improve the depth of science vocabulary knowledge. Participants included two teachers and 34 kindergartners in two rural public schools. During an eight-week intervention period, participating teachers read a different information book each week in an interactive manner, after which students visited a related hands-on activity center. Books and centers were grouped into pairs according to existing science curriculum requirements of Matter, Shadows, Weather, and Plant Life Cycles, so that each of the four topics was introduced and reinforced over a two-week interval. Students were engaged in teacher-led discussions and peer conversations to develop oral language, specifically depth of four science vocabulary words per interval, for a total of 16 words deeply learned over the course of the intervention. Both teachers acceptably implemented the intervention. Students were pretested before each interval's onset to determine baseline understanding of each targeted word, using study-created instrumentation for each interval. The study-created instrumentation combined receptive and expressive vocabulary measures to best meet the needs of young children. Each interval-specific form of the instrument was iteratively adapted for improved student understanding throughout the intervention. Then each child was posttested with the same instrumentation after each interval to determine growth after instruction. Dependent t-test results were favorable; students deeply learned the targeted vocabulary words. Although the results of formative research are not largely generalizable, these results suggest that a more thorough investigation of the instructional techniques implemented is warranted. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]