This progress interim report describes trends in implementation, school performance, and related factors for a sample of schools participating in the New American Schools (NAS) program. NAS is a program funding the development of designs aimed at transforming entire schools at the elementary and secondary levels. This evaluation focuses on the progress of 104 schools in 8 partner jurisdictions. Each school adopted one of seven improvement models. The report is based on a variety of data from these schools, including principal and teacher surveys (2,100 teachers) in the 1997 and 1998 school years, data about achievement test scores, and information about school demographic characteristics. The implementation of the designs was found to be higher among schools with greater experience with the design, although there was some lack of increases in implementation over time. Among the factors found to affect implementation were teacher perceptions, school characteristics, the nature of the design, design team assistance, and school district support. In the 163 schools for which achievement data were available, 50% showed gains in mathematics and 47% showed gains in reading. Overall, the analyses underscore the importance of school district environment and design team assistance in implementation of the NAS designs. Six appendixes contain supplemental information about the evaluations and the teacher and principal questionnaires. (Contains 62 figures, 24 tables, and 129 references.) (SLD)