Noting that effective writing instruction depends on careful planning informed by knowledge of the writing process and its variations in relation to different audiences and purposes, this teacher's guide explains the nature of the writing process and how it relates to instruction. The purposes of the guide are threefold: to highlight current theory and research findings on the composing process and its relation to instruction and student learning, to identify the elements of the composing process and their implications for promoting writing development in the classroom, and to offer instructional strategies to help students master varied types of writing. The sections of the first half of the guide discuss (1) writing as a recursive process; (2) postulates related to the writing process; (3) elements of the composing process using three functions of language (expressive language, transactional language, and poetic language); and (4) five elements of the composing process (prewriting, drafting, revising, editing, and post-writing stages) and their implications for instruction. The second part of the guide presents ideas for instruction within the rhetorical types of writing: narrative, descriptive, expository, and persuasive. The sections for each type of writing are divided into elementary, intermediate, and high school levels, and include a criteria worksheet and a revision checklist. Appended are a bibliography, a glossary, a list of regional curriculum service units in New Jersey, optional vocabulary choices for the revision checklists and a feedback sheet for teachers using the guide. (EL)