RAND Study Finds that Children Participating in The Big Lift Continue to Make Gains

Redwood City, CA—According to a recent RAND Corporation study, children who participated in Big Lift preschools were more kindergarten-ready than demographically similar peers who did not attend preschool, and the positive impact on students’ reading levels persisted into first grade, a promising benchmark on the path to increasing the percentage of third-graders reading proficiently at grade level, the primary goal of The Big Lift.

In the 2017-18 kindergarten class, children who received Big Lift preschool were 17 percentage points more likely to be ready for kindergarten on the Brigance readiness assessment than demographically similar peers who did not attend preschool. RAND also found that students who attended two years of Big Lift preschool were more kindergarten-ready than those who attended only one year. This was the first time RAND was able to perform this analysis. Even more significant, for the 2016-17 kindergarten class, Big Lift preschoolers had reading levels at the end of kindergarten and the start of first grade that were on par with similar peers who attended other, mostly private preschool programs, and more than half a reading level higher than similar peers who attended no preschool at all.

According to the study, “This suggests that the cognitive advantage that Big Lift preschoolers had over children who did not attend preschool at the start of kindergarten persisted into early elementary school.” This is significant because research shows that in some preschool efforts, cognitive gains start to fade as early as kindergarten.

 “This report continues to show us that access to quality preschool, like that provided by The Big Lift, is critical to a student’s success later in school. The gaps we see in student outcomes start before kindergarten, so it is essential that we focus on quality programs for our youngest learners. We are thrilled to see that academic gains persist through the beginning of first grade, especially given that other similar efforts don’t always achieve this milestone,” explained San Mateo County Superintendent of Schools Nancy Magee.

As in its previous report, RAND addresses demographic differences among students covered in the study, highlighting that for “nearly all demographic indicators, children in The Big Lift preschool group were more disadvantaged than their peers.” More than 70 percent of Big Lift preschoolers came from homes with annual incomes of $50,000 or less, compared with less than one-third of children in the comparison groups. They were also more likely to come from single-parent homes and have parents with lower levels of formal education.

“The RAND study shows that through The Big Lift, we are on the path to closing opportunity gaps in our county. Our task now is to continue to follow and support these children through third grade,” added San Mateo County Supervisor Carole Groom.

The study is the second in RAND’s multiphase, independent evaluation of The Big Lift initiative. The first study examined the early education experiences and kindergarten readiness outcomes of children in the 2016-2017 kindergarten class who received Big Lift preschool. RAND’s reports can be used to track trends over time and help Big Lift stakeholders understand the efficacy of the program and make informed decisions on how best to serve their communities.

The Big Lift is a preschool to third grade initiative in San Mateo County, California that uses a collective impact approach. Launched in 2012 by the County of San Mateo, the San Mateo County Office of Education, and the Silicon Valley Community Foundation, the initiative aims to boost third grade reading proficiency through a set of four coordinated strategies, called “pillars”: 1) High-Quality Preschool; 2) Summer Learning; 3) School Attendance; and 4) Family Engagement. The Big Lift is working intensively with 96 preschool classrooms serving 2,000 children annually in seven school districts to improve quality, deepen family engagement, and help ensure more children from vulnerable groups arrive at kindergarten ready to thrive in school. It also serves 1,200 incoming kindergartners through second graders annually through its Inspiring Summers program, and thousands more through attendance messaging efforts. 

The RAND Corporation is a nonprofit research organization that develops solutions to public policy challenges to help make communities throughout the world safer and more secure, healthier and more prosperous. RAND's research and analysis address issues that impact people around the world including security, health, education, sustainability, growth, and development. Much of this research is carried out on behalf of public and private grantors and clients.


The San Mateo County Office of Education is committed to ensuring excellence and equity in education by inspiring students, investing in teachers,  invigorating leaders, and involving communities.