Little research has examined the school experiences of lesbian/gay (LG) parent families or adoptive parent families. The current exploratory study examined the experiences of 79 lesbian, 75 gay male, and 112 heterosexual adoptive parents of preschool-age children with respect to their (a) level of disclosure regarding their LG parent and adoptive family status at their children's schools; (b) perceived challenges in navigating the preschool environment and advocating on behalf of their children and families; and (c) recommendations to teachers and schools about how to create affirming school environments with respect to family structure, adoption, and race/ethnicity. Findings revealed that the majority of parents were open about their LG and adoptive family status, and had not encountered challenges related to family diversity. Those parents who did experience challenges tended to describe implicit forms of marginalization, such as insensitive language and school assignments. Recommendations for teachers included discussing and reading books about diverse families, tailoring assignments to meet the needs of diverse families, and offering school community-building activities and events to help bridge differences across families. (author abstract)