Almost no research has examined the role of parent-school relationships in relation to child psychological functioning in adoptive families or same-sex parent families, much less same-sex adoptive families. Yet adoptive families, and particularly same-sex adoptive families, may be vulnerable to marginalization in the school setting, which could have implications for child adjustment. Using parent reports, in a sample of 106 lesbian, gay, and heterosexual adoptive parent families with young children ([mean]age =3.38 years at T1 and 5.42 years at T2), this study examined T1 parent-school relationships (school involvement, parent-teacher relationship quality, parent-school contact about child problems, and perceived acceptance by other parents) and adoption-specific school experiences at T1 (i.e., parent input about classroom inclusion and parent-teacher conflicts related to adoptive family status) in relation to children's later (T2) internalizing and externalizing symptoms, controlling for T1 symptoms. Follow-up analyses assessed these predictors in relation to concurrent (T1) symptoms. Family context and demographic variables were included as controls. Parents' school involvement was negatively related to later internalizing symptoms; providing input to teachers about inclusion, and parent-teacher conflicts related to adoption, were both positively related to later internalizing symptoms. Perceived acceptance by other parents was negatively related to later internalizing and externalizing symptoms. School-initiated contact about child problems more strongly predicted higher externalizing symptoms in same-sex parent families than heterosexual parent families. Cross-sectional analyses (T1 predictors in relation to T1 child outcomes) revealed a somewhat different set of findings: most notably, parents' school involvement was negatively related to externalizing symptoms. Findings have implications for early childhood educators and school administrators who seek to improve diverse family-school partnerships to enhance children's emotional and behavioral well-being. (author abstract)