Important new research out from the Frank Porter Graham Child Development Institute at the University of North Carolina. From a press release:

Contrary to conventional wisdom, English-only pre-kindergarten classrooms may not help native Spanish-speaking children become better prepared for school. According to research by FPG Child Development Institute at the University of North Carolina at Chapel Hill, Spanish-speaking children had better social skills when their teachers spoke some Spanish.

“Many early childhood programs are moving toward a system that may isolate children who are learning English, leaving them at risk for social and language problems,” said an author of the study, Gisele Crawford, a research associate at FPG. The study will be published in the April issue of Early Education and Development.

“Programs that have the potential to mitigate the achievement gap between children from different racial, ethnic and socioeconomic groups may be doing just the opposite. This study suggests that, too often, iniquities already are present in early educational experiences between non-English speaking and English-speaking children,” Crawford said.

Why is this important? One word: Demographics. Twenty percent of children in the U.S. aged zero to eight are Hispanic, 90% of them American citizens. Here's more information from the National Task Force on Early Childhood Education for Hispanics.