This article discusses a variety of open resources that can be used to teach mycology. Many schools may not routinely teach a mycology class -- and if they do, students might not want to invest in a textbook. Options for resale are probably much smaller than with a class in which more students routinely enroll. This article is important in showing both students and faculty how much information about fungi is available online. Some websites are transient, so the reader must carefully check them before use. The sites selected cover most topics that are typically covered in a mycology class. However, depending on faculty emphasis, not all of the information presented in the article may be relevant. These resources should enable faculty to achieve the major teaching objectives in a mycology class, enabling students to gain an appreciation of the diversity of fungi and a basic understanding of their biology, ecology, genetics, morphology, and taxonomy.