They'll flail a lot and tire themselves out and if necessary a few punches from the top controlling position will show them the need to calm down. This happened a lot growing up...been there, done that.

Most often even if the other guy has their friends/posse with them they see how easy it went and see that I'm not being overly viscous to their guy and likewise realize they wouldn't want any of it either so they start to encourage their guy to calm down so I'd let them go.

This only becomes a problem if the friends/posse decide to jump in and nobody has my back at all. Which has also happened a few times and I've done alright for myself most of those times.

Kids today have no idea what it was like to have to fist fight just to get to school. Coming from a bad neighborhood with a lot of illicit activity and violence that bled all the way down to elementary age kids is rough.