Given these positive findings, this report describes the High 5s program in detail, noting what was needed to implement the program with fidelity. Because the High 5s program was new and developed specifically for this project, and because it set out to achieve an ambitious set of logistical and educational objectives, it was not clear at the outset whether it could be implemented successfully. In the end, the program, supported by a strong, ongoing training and supervision model, was generally implemented with fidelity to the model. The program was also found to differ substantially from the math instruction already in place in kindergarten classrooms, suggesting that the High 5s program may have provided substantial added value to the children's kindergarten math experiences. A number of important lessons about implementation, attendance, and student engagement are described in this report. Chapter 2 describes the structural components of the program, and Chapter 3 details the staffing and associated training and supervision. The quality and fidelity of implementation is assessed in Chapter 4, and the math environment and instruction in the kindergarten classrooms are described and compared with High 5s in Chapter 5. The report concludes with a discussion about what might be needed to replicate the program in other contexts. (author abstract)