Lipid rafts have been implicated in numerous cellular processes including cell signaling, endocytosis, and even viral infection. Isolation of these lipid rafts often involves detergent treatment of the membrane to dissolve nonraft components followed by separation of raft regions in a density gradient. We present here an inquiry-based lab series using these techniques to isolate membrane rafts from yeast cells designed for the upper division biochemistry or cell biology course laboratory. The co-localization of a common raft-associated protein with lipid rafts is then followed. This lab series involves undergraduate cell biology or biochemistry students in each step of the scientific process from experimental design to dissemination of their results. Additionally, this lab series reinforces concepts in membrane structure while exposing undergraduates to common techniques in cell biology and biochemistry. (Contains 3 figures and 1 table.)