San Diego State University Research Foundation will examine the potential efficacy of a focused vocabulary and oral language intervention for improving the academic readiness (VOLAR) of preschool Latino English Language Learners (ELL) within the preschool curriculum. The project's goals are to: (a) evaluate whether a focused and direct vocabulary and oral language instruction facilitates children's academic readiness compared to children who do not receive the VOLAR intervention; (b) evaluate the effect of time of intervention; and (c) determine the extent to which the interventions can be implemented independently and successfully by Head Start teachers. Participants will include 120 4-year-old ELL Spanish-speaking children and their families. In Year 1, children's growth in English and Spanish was assessed using measures of vocabulary, language, and academic readiness. In Year 2, children were randomly assigned to a fall or spring experimental VOLAR group. In Year 3, the VOLAR intervention will be implemented by Head Start teachers. It is expected that the VOLAR intervention will result in a vocabulary and oral language curriculum for preschool ELL children that can help Head Start teachers meet the needs of ELL children. In addition, the VOLAR intervention is expected to contribute critical knowledge for the development of future vocabulary and language curriculum evaluation studies to address the needs of ELL children from other language backgrounds.