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Research Brief

Key Findings

  1. During the 2015–2016 school year and the following summer, Big Lift served approximately one-third of the entering 2016–2017 kindergarten class in four Big Lift participating districts.
  2. In the 2016–2017 school year, 50 percent of kindergartners in Big Lift districts scored in the kindergarten-ready range on a school readiness assessment at the start of the year.
  3. When comparing demographically similar children, Big Lift preschoolers were more likely to be kindergarten-ready than children who did not go to preschool at all.Big Lift preschoolers and non–Big Lift preschoolers were equally likely to start school kindergarten-ready.

The Big Lift™ (Big Lift) is a preschool–third grade collective impact initiative in San Mateo County, California, launched in 2012 by the County of San Mateo, the Silicon Valley Community Foundation (SVCF), and the San Mateo County Office of Education (SMCOE). The initiative aims to boost third-grade reading proficiency through a set of coordinated activities, called "pillars": (1) High-Quality Preschool; (2) Summer Learning; (3) School Attendance; and (4) Family Engagement.

The RAND Corporation is conducting a multiphase independent evaluation of Big Lift. This brief summarizes results from RAND's descriptive analysis of participation rates and school readiness outcomes for children served in the first year of the initiative by two of the four pillars for which data were available: High-Quality Preschool and Summer Learning. The study specifically examined three topics for the first cohort of entering kindergartners to experience Big Lift services: participation rates in Big Lift services in the prior year, kindergarten readiness indicators overall, and differences in readiness based on the type of early learning experience they had.

The ongoing evaluation will build upon this baseline study to provide additional information on the reach and effectiveness of the Big Lift pillars and help community stakeholders make informed decisions as the initiative matures.

Big Lift Preschool and Summer Learning Services

As part of the High-Quality Preschool pillar, Big Lift funds were used to increase both the availability and quality of preschool programs in participating districts. Big Lift preschool programs serve three- and four-year-olds and represent a range of different center-based early care and education programs. All programs receive targeted coaching on instructional practices, professional development supports, and technical assistance to improve quality over time.

the San Mateo County Library, and participating school districts. The program includes language and literacy instruction, as well as science, technology, engineering, and math (STEM) learning activities.

This initial descriptive study examined data from kindergartners served by Big Lift preschool and BLIS in the first round of Big Lift school districts — Cabrillo, Jefferson, La Honda-Pescadero, and South San Francisco — referred to as "Cohort 1" and funded in spring 2015. The sample includes 1,496 children, representing 99.6 percent of the 2016–2017 kindergarten class in the Cohort 1 districts, as of September 2016.

Participation in Big Lift Services

The RAND researchers analyzed participation in Big Lift services — including Big Lift preschool and BLIS — for the 2016–2017 kindergarten class in the Cohort 1 districts. These data show the following participation patterns:

  • Big Lift Preschool: 23 percent of kindergartners received Big Lift preschool the prior year. Another 54 percent of children enrolled in other early education programs (i.e., non–Big Lift preschool), for a total of 77 percent of children with some type of preschool experience in the year before kindergarten.
  • Big Lift Inspiring Summers: 22 percent of kindergartners participated in BLIS in the summer before kindergarten.
  • Any Big Lift Service: Taken together, 35 percent of kindergartners in Cohort 1 districts received at least one Big Lift service — either Big Lift preschool, BLIS, or both. In line with the initiatives' priorities, Big Lift served a large percentage of children from lower-income families. Therefore, children served by Big Lift were more disadvantaged than their peers in the county.

Kindergarten Readiness in Big Lift Districts

As part of the collective impact collaborative, the Cohort 1 districts administered a common kindergarten entry assessment, the Brigance Early Childhood Screen III, to all entering kindergartners in the 2016–2017 school year. Data for this study were collected at the start of the school year and include child-level Brigance data and data on parent-reported, child-level home reading practices: the number of books in the home and how often families read to children.

Analysis of these measures of kindergarten readiness shows the following:

  • Approximately 50 percent of the 2016–2017 kindergarten class scored in the kindergarten-ready range on the Brigance.
  • 60 percent of children had 20 or more books in the homes and 27 percent of children were read to daily.

Differences in Kindergarten Readiness by Preschool Participation Status

Using regression analysis, the RAND researchers compared demographically similar children who went to Big Lift preschool, non–Big Lift preschool, and no preschool at all on the Brigance and the home-reading practices. Researchers controlled for such characteristics as family income, parent education, and other factors related to children's development and families' preschool choices. Although this analysis does not measure whether differences in readiness can be attributed to Big Lift preschool participation, it does demonstrate how these important indicators vary across children with similar family and home environments but different early learning experiences.

When comparing Big Lift preschoolers with children who attended no preschool at all, Big Lift preschoolers were significantly more likely to start school scoring in the kindergarten-ready range on the Brigance and more likely to have 20 or more books in the home and be read to daily. The figure below displays the comparisons between Big Lift preschoolers and children who did not attend preschool. All comparisons showed statistically significant differences that favored Big Lift preschoolers. For example, when controlling for demographic characteristics, significantly more Big Lift preschoolers — a difference of 27 percentage points — started school kindergarten-ready.

Big Lift preschoolers and non–Big Lift preschoolers were equally likely to start school kindergarten-ready, come from homes with 20 or more books, and to be read to daily. There were no statistically significant differences between Big Lift preschoolers and children who attended other preschool programs on any of the three outcomes.

  • This research was commissioned by The Big Lift and Silicon Valley Community Foundation with generous funding from the County of San Mateo and the federal Social Innovation Fund.

This report is part of the RAND Corporation Research brief series. RAND research briefs present policy-oriented summaries of individual published, peer-reviewed documents or of a body of published work.

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