Science/Technology/Society STS) has been defined as teaching and learning in the context of human experiences. The STS movement has grown out of dissatisfaction with the curriculum reform of the 1960s and utilizes a problem solving approach that appeals to students' interests. This paper describes the STS approach and reports research results comparing STS and non-STS approaches to science instruction. The paper has six distinct purposes as follows: (1) to identify urgent problems related to school science teaching; (2) to describe how the STS approach can help solve these problems; (3) to describe the Iowa STS model and goals; (4) to give concrete examples of the use of STS in the classroom; (5) to report the results of four studies evaluating learning outcomes in STS courses; and (6) to identify some problems concerning the future use of STS. To meet these purposes, nine urgent problems related to the teaching and learning of science are identified and a discussion of how the STS approach would solve those problems is provided. Following this, a unique inservice teacher model to disseminate the STS approach called the Iowa Chatauqua Model is described. Five of the six major goals of this model are described in depth. Characterized as "domains," they are: (1) concept; (2) process; (3) applications; (4) creativity; and (5) attitude. The four studies assessing the impact of the STS approach on each of these domains are discussed next. The studies examined K-12 teachers (n=176) who had completed all aspects of the Iowa Chautauqua Program for 1988-89, and compared results of STS and non-STS students in grades 4-9 and student teachers in Taiwan. Results from the four studies indicated that no statistically significant differences were found in achievement in the concept domain. In the four other domains, strong differences were found in creativity and process domains for grades 4 and 5, in the application domain for grades 8 and 9, and for low ability students in the attitude domain. STS had a strong positive effect on the attitudes of females toward science. Finally, implications of these results in the areas of curriculum reform, assessment, STS, and the professional development of teachers are discussed and it is concluded that the four studies provide "hard" empirical evidence in favor of the STS approach for schoolchildren as well as for teachers. As regards purpose number 6, "problems," these are outlined very briefly in terms of activities considered to be important for future research. (Contains 33 references.) (MDH)