Nuffield Secondary Science is a set of tested materials from which teachers can prepare courses for students in grades 9-11 (approximately) who do not intend to major in science. The materials are designed for British secondary schools but are adaptable to other countries. The Teachers' Guide to the entire set of Themes is described in SE 015 440 and the nature of each Theme summarized in SE 015 441. Theme 4 contains the following fields of study (with subsidiary sections indicated in parentheses): Energy in Action (energy conversion, energy and movement, energy and changes in materials); Man's Energy: His Physical Limitations and the Use of Machines (exerting and measuring forces, exerting forces by simple machines, doing work in simple situations, physiological effects of doing work, power output of human body, power of engines and motors, working through machines); Electrical Transmission of Energy (introductory investigations, versatility of electricity, simple d.c. circuits, use of alternating current, motors and dynamos, converting a.c. and d.c.); and Problems of Bringing Energy to Bear (heat, entropy, efficient use of fuels). See also SE 015 442 to SE 015 448. (AL)