This study estimates the costs of providing a high-quality PreK-3rd education approach in all 50 states plus the District of Columbia. Relying on an Evidence-Based approach to school finance adequacy, it identifies the staffing resources needed to offer high-quality integrated PreK-3rd programs and then estimates the costs of those resources. By developing a highly flexible model, it is possible to simulate alternative staffing resource configurations for PreK-3rd programs providing a state-by-state estimate of the cost to implement the program. If it is assumed that 65 percent of three- and four-year-old children will participate in PreK programs, the estimated additional cost of providing the resources for PreK-3rd ranges from $28.4 billion, if eligibility is limited to three- and four-year-olds at 100 percent of the federal poverty level, to $78.7 billion if PreK is universally available to three- and four-year-olds. These costs range from $2,237 to $3,975 per student served, and vary considerably by state. These state-by-state estimates can be further refined by using more detailed individual state data systems, if they are available. (Contains 5 tables, 1 figure, 3 footnotes and 11 online resources.)