The plasma membrane is the membrane that serves as a boundary between the interior of a cell and its extracellular environment. Lipid rafts are microdomains within a cellular membrane that possess decreased fluidity due to the presence of cholesterol, glycolipids, and phospholipids containing longer fatty acids. These domains are involved in many different plasma membrane functions, including cell signalling. Knowledge of the structure and function of the plasma membrane is required in order to comprehend complex cellular processes such as migration and signal transduction. This knowledge is often acquired during university through introductory biology courses or cell/molecular biology core courses. Since active learning has been shown to facilitate student learning, it follows that this style of teaching may enhance lectures based on the topic of the plasma membrane. Unfortunately, few plasma membrane specific activities exist for university-level classes. This article presents an activity titled "You Sank My Lipid Rafts," which the author developed and modeled after the board game titled "You Sank My Battleship" from Milton Bradley and Hasbro Games. Taylor and Busto (2004) suggested the use of the Battleship game to teach plotting of coordinates for students in grades three through four. The Battleship game can also be used as a tool for older students. Hence, You Sank My Lipid Rafts was carried out in a third year course titled Honours Cell and Molecular Biology (Medical Science 351, Bachelor of Health Sciences Program) at the University of Calgary (Calgary, Alberta, Canada). (Contains 4 figures.)