In this study the feasibility and educational value of students' writing their own textbook was explored for a particular course in which commercial textbooks had become a normal feature. The course itself was about introductory educational psychology--a common requirement for preservice teachers in training. In lieu of buying a commercial text, students developed a table of contents for 2 editions of their own text, posted and edited sections of chapters, and assessed the results. Although the resulting books were shorter than major commercial textbooks and obviously lacked their "production features," they offered important clues to students' educational priorities. Both in choosing topics to write and in reading each other's work, students emphasized certain topics (e.g., special education and classroom management) more than did authors of commercial texts and reduced coverage of other conventional topics (e.g., instructional planning and assessment of learning). Overall, the results suggested educational advantages to students' writing their own textbooks, as well as areas where commercial publishers can make their textbooks more relevant and motivating. At the same time, however, student-written texts raised questions about coverage of content and the role of student input guiding content. (Contains 4 tables and 2 notes.)