In addition to Sabin House, Lawrence provides alternative housing for upperclass students in eight small residential houses at various locations bordering the main campus. The houses have accommodations for between ten and 18 students. Some houses are designated as "theme houses," available through a campus lottery to groups working toward common interests and goals. Groups that have occupied these houses in the past have been organized around such themes as community service, the study of a language, an interest in women's issues, and ecology. The Co-op House at 122 North Union Street provides a cooperative living environment in which students do their own shopping and cooking.