Based on two national assessments of the writing proficiency of representative samples of students in grades 4, 8, and 11 conducted during the school years ending in 1984 and 1988, this report assesses the informative, persuasive, and imaginative writing performance of the nation's students and tracks changes in performance over time. The first three chapters of the report describe student performance on the informative, persuasive, and imaginative writing tasks included in the writing trend assessments, based on the results of the primary trait and holistic analyses. The fourth chapter summarizes trends in average task accomplishment for the nation and various demographic subpopulations. In the fifth chapter, trends in students' grammar, punctuation, and spelling are discussed. The sixth chapter discusses factors that appear to be related to writing performance, such as students' instructional experiences and home environment. The report concludes that despite some progress on some tasks, students' writing performance across tasks remains low and has changed little across time. The report also finds that the extent to which students at all grade levels value writing, use it in their own lives, and engage in writing process activities remains quite limited. (A procedural appendix and an appendix of data are attached.) (RS)