Division of fractions is often considered the most mechanical and least understood topic in elementary school. Enacting fraction division tasks in meaningful ways requires that teachers know not only "how" fraction division works but also "why" it works. The authors have created materials to help preservice teachers develop that knowledge. To provide sufficient time for the learners to engage and struggle with cognitively demanding tasks, just one or two complex problems are explored during one-hundred-minute periods. Various instructional strategies are used to elicit multiple solution methods and representations and to press for justifications of solutions, modeling the type of instruction these teachers could use with their future students. This article presents a sequence of tasks that is designed to promote an understanding of fraction division, and brief vignettes explore their implementation. In particular, following a discussion of prerequisite experiences in whole-number division, two types of fraction division activities are addressed: (1) those helping build the concept of the unit; and (2) those helping connect representations. Although these tasks were implemented with preservice teachers, examining these tasks may help in-service teachers deepen their own understanding of fraction division. Further, the activities provide seeds for mathematical tasks that teachers might enact with middle school learners. (Contains 6 figures.)