The primary aim of this study was to identify particular group configurations and teacher behaviors that co-occurred with children's active engagement in public school early childhood classrooms for 4-year-olds. Children (N=138, 52% boys) were observed using a time sampling method in 12 classrooms in 12 urban schools serving students from predominantly lower-income, minority families. Children were involved in whole group settings for 52% of observations. The most common teacher behavior in any setting was providing direction/instruction. Logistic regression analyses indicated that, during academic activities, children were more likely to be actively engaged when involved in a peer group and when teachers were providing affirmations or were monitoring, and least likely to be actively engaged in a whole group and when teachers were providing directions. During play activities, children were more likely to be actively engaged when they were alone and least likely to be engaged in a whole group and in a child-teacher setting.