British science curriculum improvement projects on the elementary and secondary school levels are reviewed in this volume to indicate their implications for the development of second-generation programs in the United States. Included in the British second-generation program category are: the Scottish integrated courses, Nuffield combined science, Nuffield secondary science, and the Schools Council integrated science project. Detailed descriptions are given to these more-or-less unified programs in terms of course objectives, course construction principles, teaching techniques, materials available, and current status. To provide perspective, a brief summary is also made of other British projects: Nuffield O level schemes, Nuffield A level science project, Science 5/13 (for 5- to 13-year-olds), Nuffield Junior Science Project, Scottish science, Schools Council Project Technology, and Biology for the Individual. Differences between curriculum projects in Britain and the United States are examined in terms of project initiation, program flexibility, and financial support. Also included is a bibliography of publications referred to in the projects, with publishers' addresses incorporated at the end. (CC)