Two booklets were developed by the Learning in Science Project (Primary)--LISP(P)--to help teachers adopt an approach to primary science teaching which would enhance children's understanding of floating and sinking. Both booklets were designed to enable teachers to reconceptualize their teaching task from activity-driven, didactic teaching to conceptual-change teaching. The first booklet (dated November 1983) was written for teachers preparing detailed guidance. The second booklet (dated February 1984) was written for more confident teachers, using a less structured approach. The earlier version emphasizes floating and sinking and contains: (1) information about the ideas that children hold on this topic; (2) information about the ideas that scientists hold on the topic; and (3) suggested investigations, experimental projects, and non-experimental projects to help children move gradually from intuitive explanations toward those which will ultimately be more useful to them. The investigations are designed to examine which materials float, if holes in floating materials affect their floating, if the depth of water affects floating, and if the length of an object affects its floating. The experimental projects are designed to examine how non-floating materials can be made to float, how a sunken object can be raised, which material is the best floater, and the amount of water displaced by the same object while floating or sinking. The non-experimental projects are used to examine practical applications of floating and sinking. Each investigation or project includes suggested procedures and statements of both children's and scientists' views of the particular phenomenon under consideration. The later booklet emphasizes a general approach to science teaching and contains a five-step approach that helps students to: acquire scientific understanding and knowledge for themselves at their level; ask genuine questions; seek more information; test out their present ideas; construct reasoned explanations; and develop scientific attitudes. The instructional tasks involved in the five steps include: (1) eliciting and recording children's questions; (2) helping children decide which questions should be investigated; (3) assisting them in planning their investigations; (4) providing assistance during their investigations; and (5) helping them record and report their findings. A set of teacher's notes on "floating and sinking" is provided in an appendix. These notes include information on scientists' and children's explanations of floating and sinking, a list of questions children aged 9-12 most often ask about the topic, and suggestions for initiating activities to focus children's questions about various aspects of floating and sinking. (JN)