New Study Shows High Quality State Pre-K Programs Improve Language and Math Abilities of Children of All Backgrounds

A new study of high quality prekindergarten programs in five states reveals significant improvement in children's early language, literacy and mathematical development, improvement far greater than found in a recent national study of the federal Head Start program.

The study finds that children attending state-funded pre-k programs in the five states (Michigan, New Jersey, Oklahoma, South Carolina, and West Virginia) gained significantly regardless of ethnic background or economic circumstances. 

The study, The Effects of State Prekindergarten Programs on Young Children's School Readiness in Five States, was conducted by The National Institute for Early Education Research (NIEER) at Rutgers University with support from The Pew Charitable Trusts and the Joyce Foundation. The study was authored by W. Steven Barnett, Cynthia Lamy and Kwanghee Jung.

“This study provides strong evidence that quality public preschool programs produce broad gains in children's learning and development,” Barnett said. 

"What this study shows is that investments in pre-K are not just good for the child but good for the state, the city, and for the country," said Sue Urahn, director, state policy and education, The Pew Charitable Trusts. "Investing in pre-k returns an investment to all of us."  

The study estimated the effects of preschool programs on entering kindergartners' academic skills. Vocabulary and early literacy skills were tested in all five states; math skills in all states except South Carolina. With the cooperation of education officials in the five states, researchers collected data on 5,071 preschool and kindergarten children in 1,320 classrooms in the fall of 2004. Children were tested in English or Spanish depending on their strongest language.    

“We found these state-funded preschool programs to have statistically significant and meaningful impacts on children's early language, literacy and mathematical development,” the researchers wrote. Their key findings were:  

Children who attended state-funded preschool showed gains in vocabulary scores that were about 31 percent greater than gains of children without the program. This translates into an additional three months of progress in vocabulary growth due to the preschool program at age 4. This outcome is particularly important because the measure is strongly predictive of general cognitive abilities and later reading success, the researchers said.

State-funded preschool increased children's gains in math skills by 44 percent compared to children's growth without the program. Skills tested included basic number concepts, simple addition and subtraction, telling time and counting money.

State-funded preschool produced an 85 percent increase in growth in print awareness among children enrolled compared to growth of children without the program.Children who attended a state-funded preschool program before entering kindergarten knew more letters, more letter-sound associations and were more familiar with words and book concepts. 

These results come at an opportune time for early education advocates. Earlier this year, the Head Start National Impact Study reported no statistically significant effects for 4-year-olds on vocabulary or early math scores. 

“Using identical or similar tests, the NIEER studies show vocabulary gains three or four times greater than those in the Head Start study,” Barnett said.

“This difference in outcomes between the two types of programs points to the likely effects of the higher qualifications (and higher compensation) of teachers in state prekindergarten programs compared to Head Start,” Barnett and his colleagues wrote. “We believe Head Start and other state programs could produce gains similar to those we found if they were able to hire highly qualified teachers.The state prekindergarten programs we studied do not uniformly differ from Head Start with respect to other characteristics such as length of day or class size.”

The five states studied almost universally require prekindergarten teachers to be licensed teachers with BA degrees and certification in early childhood education. Head Start requires that 50 percent of teachers have two-year Associate's degrees and the others must have a Child Development Associate (CDA) credential or its equivalent. A CDA represents 120 clock hours of training.Congress is considering Head Start reauthorization legislation that for the first time would require some percentage of teachers to have BAs.

“Comparisons to Head Start suggest that both Head Start and state preschool programs with weak standards for teacher qualifications (and low teacher pay) might increase their effectiveness by raising their teacher qualifications standards and compensating teachers accordingly,” Barnett and his colleagues wrote.

Forty states have state-funded prekindergarten programs. The standards and quality, as well as the population served vary greatly. The five states in this study rank among the highest in NIEER's annual evaluation of state prekindergarten programs. Most state prekindergarten programs target children who are at elevated risk of school failure (often due to poverty), and programs for these children have been the most studied.  

Less research has been conducted on the impacts of programs for children who are not economically disadvantaged. With a number of states now making prekindergarten education available to all 4-year-olds, the NIEER study sought to address the impact of prekindergarten on children from every economic level.

Two of the programs in the study—Oklahomaand West Virginia—offer services to all children regardless of income. “When we compared results for children who had subsidized lunches with those who didn't, we found that all children gained from attending pre-k, but there was some evidence that children who qualified for free or reduced price had larger gains,” Barnett said.  While there were differences in scores among children of various backgrounds, all children gained, regardless of ethnic background.  The sample used for the study was 47 percent White, 25 percent African American, 21 percent Hispanic, 3 percent Native American and 2 percent Asian.

A large body of research shows that high quality preschool programs can lead to increases in school success, higher test scores, fewer school dropouts, higher graduation rates, less special education and even lower crime rates.