Reflecting changes in the focus and methodology of writing research over the past 20 years, this book provides a meta-analysis of studies on teaching approaches and focuses on composition instruction at the elementary, secondary, and college levels. The first chapter of the book examines general studies of the composing process, studies of process in classrooms, and studies of planning, production factors, revision, and writing apprehension. Summaries of the limitations and key findings of the research on process are included. The second chapter explores research on the repertoire of lexical, syntactic, or rhetorical forms which writers call upon in their writing. The third chapter examines criticisms of experimental studies and the difficulties in doing them, then explains the techniques used in the meta-analysis of such studies, the selection of studies, and the variables examined. The next four chapters analyze the studies in the areas of modes of instruction, grammar and the manipulation of syntax, criteria for better writing, and invention. The eighth chapter presents the results of the meta-analysis for the dimensions examined: grade level, duration of treatment, mode of instruction, focus of instruction, revision, and feedback. The final chapter discusses the compatibility of results of treatment or method studies with those of processes studies, and offers recommendations for future research. (HTH)