This evaluation report investigates the effectiveness of the Unified Science and Mathematics for Elementary Schools (USMES) program during the academic year, 1973-74. USMES is a curricular program designed to develop the problem solving abilities of students attending grades one through eight. The goal of the program is the development of 32 interdisciplinary units engaging the student in long-range investigations of real and practical problems taken from his or her school or community environment. These areas were identified as high priority issues during the first year of a comprehensive program evaluation: actual usage, proof of concept, materials, teacher training, and indirect effects. Once these issues were specified, the evaluators selected the following indicators through which they would gather the required data: (1) a test especially designed for assessing problem solving abilities; (2) selected subtests of the Stanford Achievement Test; (3) observational scales for classroom activity analyses; (4) questionnaires surveying how the teachers were implementing the USMES program; (5) direct interviews with USMES teachers, principals, district level administrators, and leaders of district resource teams who would train USMES teachers; and (6) on site visits for unstructured observations and interviews to determine the actual patterns of program adoption or adaptation. Following an initial overview, chapters two through six address each issue, one by one. A concluding chapter then summarizes, offers specific conclusions, and makes recommendations for the future development and implementation of the USMES program. (RC)