Strengthening Head Start: What the Evidence Shows. The right programs and training can improve childrens school readiness


Research, though limited, clearly demonstrates the value of providing comprehensive interventions with strong language and pre-academic components that develop the knowledge and skills necessary for kindergarten and the early grades and for closing the achievement gap. Though more research is needed, a few approaches that have been evaluated using rigorous designs show that comprehensive and language and literacy-rich early childhood programs can reduce achievement gaps for disadvantaged children. Here are highlights of major studies.(35)

The Chicago Child-Parent Center (CPC) Program

This program for low-income minority children in high-poverty neighborhoods in inner-city Chicago, funded in part by the Department of Education, includes half-day preschool for one or two years, full or part-day kindergarten, continuing support services in linked elementary schools, and a parent education program. The Chicago CPC program provides educational and health and nutrition services, such as hearing screening, speech therapy and nursing services, to children ages 3 to 9 years. The intervention emphasizes the acquisition of basic knowledge and skills in language arts and mathematics through relatively structured but diverse learning experiences. An intensive parent program includes volunteering in the classroom, attending school events and field trips, and completing high school. Teachers are required to have bachelors degrees, are paid at the level of teachers in public school, and participate in regular staff development activities. Child-to-staff ratios are low (17:2).

A longitudinal study funded by the National Institutes of Health and other funders compared participant children to a non-experimental comparison group of children with similar demographics. Findings include:

Reading and Mathematics Achievement. At the end of the program in third grade, CPC graduates surpassed their comparison group counterparts by 4 to 6 points in reading and mathematics achievement, as measured by the Iowa Test of Basic Skills.(36)

Preschool participation. One or two years of CPC preschool participation was associated with statistically significant advantages of 5.5 and 4.2 points in standard scores for reading achievements for ages 14 and 15. This corresponds to about a 4- to 5-month change. Likewise, preschool participation was significantly associated with a 4.4-point increase in standard scores in math achievement at age 14 and a 3.3-point advantage at age 15, above and beyond gender, environmental risk factors, and participation in follow-on interventions. This translates into a 3- to 4-month performance advantage over the comparison group. These effect sizes are considered moderate; however the effects persist up to 10 years after children leave the program, which is unique among early interventions and almost all social programs.(37)

Follow-on participation. Because the early childhood program is linked to the kindergarten and elementary schools, children may participate in the program from 1 to 6 years. Each year of participation was associated with an increase of 1.3 to 1.6 points in the standard score for reading. Years in the follow-on intervention were significantly associated with reading achievement at ages 14 and 15 and went beyond that attributable to preschool participation. The most dramatic effect occurring after 4 years of intervention: Five or six years of participation resulted in the best performance, with children performing at or above the Chicago averages in reading and mathematics. (Even 6 years of participation, however, did not elevate the performance of the maximum intervention group to the national average.) A similar pattern occurred for mathematics achievement, though the size of the effect was smaller.(38) The findings showed that the relationship between years of participation and school achievement is not strictly linear  greater advantages accrue as the length of the intervention increases.

Other Outcomes. Preschool participation was associated with lower rates of grade retention (23% vs. 38.4%) and special education placement (14.4% vs. 24.6%). Preschoolers who participated in the intervention spent an average of 0.7 years in special education compared with 1.4 years for non-participants.(39) Children who participated in the preschool intervention for 1 or 2 years had a higher rate of high school completion (49.7% vs. 38.5%), more years of completed education (10.6 vs. 10.2), and lower rates of juvenile arrests (16.9% vs. 25.1%).(40) Boys benefited from preschool participation more than girls, especially in reducing the school dropout rate.(41)

Cost-benefit Analyses. With an average cost per child of $6,692 for 1.5 years of participation, the preschool program generates a total return to society at large of $47,759 per participant. These benefits are the result of participants increased earnings capacity due to educational attainment, criminal justice system savings, reduced school remedial services, and averted tangible costs to crime victims. Benefits realized in each of these areas exceed the cost of just one year of the preschool program, which is $4,400. Overall, every dollar invested in the preschool program returns $7.14 in individual, educational, social welfare and socioeconomic benefits.(42)

The Abecedarian Project

The Abecedarian Project was a carefully controlled study in which 57 infants from low-income families living in a small North Carolina town were randomly assigned to receive early intervention in a high quality child care setting and 54 were in a non-treated control group. The treated children received full-time educational intervention in a high quality child care setting from infancy through age five, which included cognitive development activities with a particular emphasis on language, and activities focusing on social and emotional development. Teachers were required to have bachelors degrees and were paid at the level of teachers in public school.

Starting at age 18 months, and through follow-ups at ages 12 and 15, the treatment children had significantly higher scores on cognitive assessments. Treated children scored significantly higher on tests of reading and math from the primary grades through age 21 (though scores did not reach national averages).

At age 21, those in the treatment group were significantly more likely to still be in school and more likely to have attended a four-year college. Employment rates were higher for the treatment group than for the control group, although the trend was not statistically significant.(43)

The Perry Preschool Study

This pioneering study begun in the 1960s was one of the first to identify lasting effects of high quality preschool programs on childrens outcomes.(44) One hundred twenty-three poor African American 3- and 4-year-olds were randomly assigned either to attend a high quality preschool program or to no preschool. The two groups began the study with equivalent IQ scores and socioeconomic status. Children attended 2 ½ hour classes and teachers conducted weekly 1.5-hour home-visits.

Results showed positive impacts on several intellectual and language tests prior to school entry and up to age 7, showing that the program enhanced childrens school readiness. At age 14, participants outperformed non-participants on a school achievement test in reading, language, and mathematics. At age 19, participants general literacy skills were better than non-participants. At age 27, participants had higher earnings and economic status, higher education and achievement levels in adolescence and young adulthood, as well as fewer arrests.

Benefit-cost analyses show that by the time participants were 27 years old, the program showed a sound economic investment, with significant savings from settlement costs for victims of crimes never committed, reduced justice system costs, increased taxes paid due to higher earnings, reduced need for special education services, and reduced welfare costs.(45)

Professional Development Models

To some extent, the early childhood field has had difficulty moving forward with training in cognitive and pre-academic knowledge and skills because of a lack of understanding of how to teach this content without compromising social and emotional development. Professional development models that emphasize language and literacy development using an integrative approach to develop all areas essential to school success are effective in improving childrens school readiness.

  • A recent 2-year large-scale evaluation was conducted on the effectiveness of a professional development model for prekindergarten educators implemented in 20 Head Start programs across Texas.(46) The sites had applied to and received funding from the Texas Educational Agency for this state-initiated demonstration project.

    The design was necessarily quasi-experimental since the selection criteria allowed site directors to choose whether the site would participate as an experimental or a control site. The intervention uses an intensive mentor-coach approach to provide training and on-going support to teachers, and focuses on activities intended to target literacy and language knowledge and skills, while also promoting social and emotional development. Programs were based in school districts as well as community-sponsored daycare or freestanding Head Start agencies.

    Most mentors had a college degree, but a few had two or three years of college plus several years of experience in Head Start. Teachers received either one or two years of training. Mathematics training was offered for one year. The impact of professional development training on child outcomes differed across Head Start grantees.

    Findings for language, literacy, and mathematics. After one year of training, 43% of grantees produced impacts on childrens letter knowledge, most of these being moderate to large in size. Forty percent of grantees showed impacts on phonological awareness with most of these being moderate to large in size. Childrens ability to understand complex language was greater for 32% of the grantees and 26% produced gains in childrens usage of complex language. Fifty-five percent of grantees showed gains in receptive vocabulary and 40% showed gains in expressive vocabulary.

    After two years of training even more grantees produced impacts on childrens knowledge and skills. Eighty-four percent of grantees produced impacts on childrens understanding of complex language and 68% showed impacts on childrens usage of complex language. Seventy-five percent showed gains in receptive vocabulary and 35% produced impacts on childrens expressive language skills. Fifty-five percent showed success in promoting childrens mathematics skills, 50% promoted phonological awareness and 35% influenced letter knowledge.

    Findings for social and emotional growth. Eighty-five percent or more of teachers perceived increases in 10 of the 12 competencies that included cooperating with peers and teachers, showing independence, and engaging in conversations with friends. (No impacts were found for behavioral self-control and caring about the other persons feelings.)

    Teacher qualifications. Though significant increases in childrens knowledge and skills were obtained for teachers with two years of college education or less, stronger gains were obtained in classrooms where teachers had at least a four-year degree. Whether teacher education made a difference depended on whether teachers had one or two years of training and the outcome measured. Children whose teachers had at least a bachelors degree showed greater gains in mathematics, phonological awareness, and other complex pre-academic tasks regardless of whether teachers had one or two years of training. Children whose teachers had at least a bachelors degree showed greater gains in vocabulary comprehension, but only if they had at least one year of training.

  • The language and literacy components of the professional development program described above were also found to be effective in a small-scale study of two Title-I pre-kindergarten classrooms(47) in Texas. All teachers were credentialed with bachelors degrees and working in the Houston Independent School District. The study, which consisted of a pre-post design with a control group showed significant and educationally meaningful gains in multiple literacy and language skills. Similar to the large-scale study described above, two years of professional training led to better outcomes for children, especially in the area of language development.(48)

Lessons learned from basic and intervention research are the building blocks for both federal and state programs, as we attempt to build stronger and more seamless early childhood systems across the nation. Very few rigorous research studies exist on the effectiveness of specific curricula and approaches to instruction. Therefore, as described in the Presidents early childhood initiative, Good Start, Grow Smart, two large-scale federal efforts are underway to improve the data available on the effectiveness of early childhood curricula, early childhood interventions and programs in preparing children for school  the U.S. Department of Educations Preschool Curriculum Evaluation Research Program (PCER) and the Interagency Early Childhood Research Initiative, a joint venture among the National Institute of Child Health and Human Development and the Administration for Children and Families (ACF) within the U.S. Department of Health and Human Services (DHHS), the U.S. Department of Educations Office of Special Education Programs (OSEP) under the Office of Special Education and Rehabilitative Services (OSERS), and the Office of the Assistant Secretary for Planning and Evaluation (ASPE) also within the DHHS. Additional experimental studies are being conducted by the Head Start Quality Research Consortium.

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