Extensive research has conclusively demonstrated that children's social class is one of the most significant predictors--if not the single most significant predictor--of their educational success. This three-part study combines a statistical analysis of early skills gaps among a recent cohort of children and changes in them over time with a qualitative study of multifaceted, school-district-level strategies to narrow them. Using data from the National Center for Education Statistics (NCES): the Early Childhood Longitudinal Study of the Kindergarten Classes of 1998-1999 and 2010-2011, this study examines the relationship between children's socioeconomic status (SES) and their cognitive and noncognitive skills when starting school. Findings reveal that large performance gaps exist between children in the lowest and highest SES quintiles and that these gaps have persisted from the 1998 cohort to the 2010 cohort. The positive news is that the gaps have not grown, even as economic inequalities between these two groups of students have grown. The negative news is that the gaps have not narrowed, despite the fact that low-SES parents have substantially increased their engagement in their children's early education. This report also reviews a set of 12 case studies of communities that have employed comprehensive educational strategies and wraparound supports to provide more children (especially low-income children) with strong early academic foundations, and to sustain and build on early gains throughout their K-12 school years. Based on examples from these diverse communities, the authors discuss implications: strategies that districts can employ and district and state policy changes to make those strategies easier to adopt and more sustainable. The report ends with conclusions and recommendations for further research, practice, and policy. [For the companion report, "Reducing and Averting Achievement Gaps: Key Findings from the Report 'Education Inequalities at the School Starting Gate' and Comprehensive Strategies to Mitigate Early Skills Gaps," see ED587806.]