The lichen is an ideal subject for student study because it is omnipresent in school yards, easily collected and observed year-round, a pioneer of evolution on land, and a bioindicator of air pollution. After doing fieldwork on this unusual composite organism as an apprentice with a team of lichenologists, Sarah Thorne developed Learning Lichens. This series of four lessons uses techniques of field study and data collection, classroom lab observation, and computer-based research. The lessons are most appropriate for biology or ecology classes in grades 11 and 12 but can be adapted for grades 9 or 10. In the lessons, Thorne's students learned basic identification skills, designed an inquiry-based field investigation, and wrote up the results of their research conducted in both the classroom and outdoors in school environs. During their investigations, students grew their own lichens and became protective, proud "parents" of them.