Studies of effective early childhood curricula have shown cognitive and social benefits for DLLs that may be comparable to or greater than those for native English speakers. Researchers in Nebraska, for example, found that a professional development literacy workshop series (HeadsUp! Reading) for early childhood educators was equally effective in promoting early literacy skills for children from English-speaking and Spanish-speaking homes.
In Oklahoma, one of the pioneers of universal high-quality pre-K education, preschools produce developmental gains across various demographic groups, including Latinos, approximately 70 percent of whom come from predominantly Spanish-speaking homes. Gains for these students (in English) were stronger than for students from English-speaking homes; this might be explained by the fact that the Spanish-speaking students
began with far lower English levels than the English-speaking students