An experimental analysis of social interaction between a behaviorally disordered preschool child and her classroom peers.

The team worked in a preschool classroom. One girl rarely played with peers.

Adults gave attention to peers when they talked or shared with the girl. Later they praised the girl when she played with peers. They flipped these rules on and off four times.

The goal was to see if reinforcing peers worked as well as reinforcing the child herself.

Both plans quickly raised friendly contact. The girl talked more and peers stayed near her.

When adults stopped the rules, play dropped. When rules returned, play rose again. Either tactic—reward peers or reward the child—did the job.

Schwarz et al. (1970) tried the same idea earlier with two children with ID. They got the same lift in play, but the gain vanished when praise stopped. The 1974 study shows the same quick lift inside a real classroom.

Finney et al. (1995) moved the idea forward. Instead of praising single peers, they set a class-wide goal. Preschoolers with autism doubled their social bids and even coached one another.

Charlop et al. (1992) and Mueller et al. (2000) added peer training. They taught typical kids to comment and stay near classmates with autism. Social play rose without adult praise every minute. These later studies keep the 1974 core—peers matter—but add teaching so the help lasts.

You now have two fast levers for circle-time. Praise peers for including a quiet child, or praise the quiet child for joining. Both work right away. If you want the gain to stick, pair the praise with quick peer-training as shown in later studies. Try it Monday: pick one child who sits alone, praise the first peer who invites them to play, and watch the ripple start.