The growing importance of alternative energy sources provides an opportunity to reinforce the applicability of chemistry to the daily lives of students. In addition, they can be introduced to green chemistry and to modern analytical techniques. We have developed a two-session laboratory experiment in which students convert vegetable oil into biodiesel through a classic transesterification reaction. The product is then analyzed by GC and/or GC/MS and compared to both standards and locally purchased diesel fuel. In the course of the laboratory experiment the students are exposed to environmentally conscious chemistry, gain experience in a basic organic reaction, and utilize modern instrumentation to characterize their products.