The Extended School Year Program of the Detroit (Michigan) public schools was designed to demonstrate that lengthening the school year would produce corresponding changes in student achievement as measured by the Michigan Educational Assessment Program and the Metropolitan Achievement Test. The Extended School Year was a 3-year summer program beginning in the summer of 1995 and concluding in the summer of 1997. Elementary, middle, and high schools participated. The primary feature of the program was the addition of 15 days of instruction that meet the same purposes as the regular school year instructional program. An evaluation was conducted to collect and analyze information related to what is needed to extend the school year, and achievement data were analyzed to assess program effect. This summary presents some evaluation findings, including those from staff, student, and parent surveys. Achievement test results suggested a positive effect on scores for Grade 4. Survey data collected from teachers in all 3 summers in 16 program schools indicate a decrease in teacher support for, and belief in, the program. Approximately three-fourths of students and parents believed that the program increased students' skills. However, while 77% of parents indicated that they would like to see the program continue, 78% of students indicated that they were not happy with the program. Recommendations for program improvement are included; these center on better communication of program goals and greater involvement of parents.