Mindfulness is increasingly offered in schools around the UK, as well as internationally. Previous research has focused on the efficacy, the implementation, and the wider meaning of mindfulness in education, rather than sociological interests, such as matters of equality and social justice. This article draws on qualitative data from the 'Mapping Mindfulness in the UK' study, to investigate how mindfulness practitioners discuss and address issues of equality and diversity in relation to school-based mindfulness. Lynch and Baker's key dimensions of equality are used to analyse participants' accounts, including on adjustments to curriculum and pedagogy to accommodate diversity, practitioners' responses to socio-emotional vulnerability, and the dynamics of choice and compulsion in the classroom. By highlighting several issues of concern in these areas, the research makes original contributions to sociological understandings of mindfulness and other similar initiatives in schools, whilst offering new insights on theories of equality in education more broadly.