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Adult-child interactions which are responsive, affectionate and respectful;
Highly qualified and experienced professional educators.
Staff-to-child ratios which allow staff to interact with children.
Effective intentional curriculum that involves active engagement with children.
Space for children to have nurturing and emotionally supportive relationships with early childhood staff;
An integration between care and education;
Promotion of early literacy and math skills;
Responsiveness to cultural diversity;
High standards of safety and child protection;
An atmosphere that fosters social, emotional and regulatory skills.
… but mostly, a high quality preschool is one where families, children and visitors feel welcome and valued.
Some of this, you might say, also applies to churches: hospitality, intentionality, active engagement, literacy and responsiveness are qualities that need careful attention and cultivating.