This paper reports the findings from an Australian Research Council Linkage Project conducted in collaboration with Playgroup Victoria to promote the provision of school playgroups in practice. School playgroups are playgroups hosted by local primary schools. They are developing in popularity as part of the Early Childhood Education and Care (ECEC) pathway made accessible for children and families in their local communities. Playgroups are usually provided for families with children aged from birth to school-entry. Research shows that children who attend playgroup have better educational outcomes after the first year of school than children who do not attend. Adult caregivers (e.g. kinship members, parents, guardians) also benefit, with improved mental health and enhanced caregiving efficacy following participation. However, little is known about the specific features of school playgroups that enable beneficial outcomes for children and families, especially in terms of shared play experiences. This is significant because shared play experiences in the early years are associated with increased educational opportunities for children over the long-term. This project combined social capital theory and capabilities thinking to theorise the strength of relationships occurring between children, families, and school-staff as indicators of their capacity to support shared play experiences. The six of the 18 school playgroups that had high bonding (i.e., amongst caregivers) and high bridging relationships (e.g. caregivers and school-staff) were identified as ‘exemplar’ school playgroups. Exemplar school playgroups were intensively analysed to identify the shared features associated with their provision in practice, including their capacity to support children and families in shared play experiences. Of the six exemplar school playgroups, three were from areas of the lowest decile for socioeconomic status and parental level of education and occupation, and three from areas indicated as mid-high deciles. Two exemplar school playgroups were from regional or rural areas, and the remaining four from metropolitan. Six main features of provision were identified across all six groups, including: access to materials suitable for children’s play; a facilitator to lead and support the group; an available space within the school to host the playgroup; the school location enabling community access to the playgroups; scheduling the playgroup at times suitable for young children; and ensuring the health and safety of participants within the playgroup. Finding suggest that attending to these features in practice may help school playgroups mediate against social and educational disadvantage in their communities by enabling children and families to participate in shared play experiences.