White, C.E. and Kim, J.S., Harvard Graduate School of Education (2009). Putting the Pieces of the Puzzle Together: How Systematic Vocabulary Instruction and Expanded Learning Time Can Address the Literacy Gap. Washington, D.C.: Center for American Progress.
This report makes several recommendations to address disparities in vocabulary and spoken language based on children's family income and English-language proficiency. Schools should use systematic vocabulary instruction throughout the school day and during expanded learning time, sustain a school-wide program, regularly assess student knowledge, and help teachers target the right words during instruction. The report suggests that expanded learning time policies may enhance the effectiveness of systematic vocabulary instruction for low-income children and English language learners.