“We all like to have fun in this industry, but sometimes people go to jail,” says Sarah Diesel, an instructor at Oaksterdam University, opened in 2007 in Oakland, California. Its name is part Oakland, part Amsterdam, the Dutch city known for its permissiveness toward pot. Classes are offered in Oakland, Los Angeles and Sebastopol, north of San Francisco. Last year, it expanded to Michigan, where voters passed a medical marijuana law in 2008. They were instructed on key court decisions, how to work in a dispensary, which varieties of cannabis are best for various ailments and how to cultivate a good pot crop. Much of the school’s teaching is devoted to helping students operate within the law, while acknowledging that gray areas remain 14 years after California approved the nation’s first medical marijuana law. “If you have a grow, don’t let anyone know,” Diesel warns. In a recent Los Angeles class, there were students from states with medical marijuana laws, such as Colorado and Nevada, and states without, including Arizona, Florida, Minnesota and Texas. Everybody wants to get in.