Goodson, B., Wolf, A., Bell, S., Turner, H., and Finney, P.B. (2010). The Effectiveness of a Program to Accelerate Vocabulary Development in Kindergarten (VOCAB). (NCEE 2010-4014). Washington, DC: National Center for Education Evaluation and Regional Assistance, Institute of Education Sciences, U.S. Department of Education.
REL Southeast conducted a randomized control trial in the Mississippi Delta to test the impact of a kindergarten vocabulary instruction program on students' expressive vocabulary — the words students understand well enough to use in speaking. The study found that the 24-week K-PAVE program had a significant positive impact on students' vocabulary development and academic knowledge and on the vocabulary and comprehension support that teachers provided during book read-alouds and other instructional time.