I am a working mum to one so probably not vastly experienced in the ways of the playground.
I was at the playground yesterday with my 2 year old who was sat at the top of the slide building up courage to come down it when a big kid (about 7) came along and, without waiting or asking my fellow to get a move on, he just barged down the slide kicking his feet into my son's back. My son was absolutely shocked and distraught. He's accident prone so pretty resilient and usually picks himself up quickly but was really upset this time and I couldn't console him. The nasty big kid's mum who was sitting a good bit away but had seen everything eventually got off her ass and came over and told her kid to apologise which he refused to. I heard her giving him a "you gave the little boy a little scare and you must remember that little boys frighten easily" talk while he continued smirking.
I was absolutely livid and marched off home muttering under my breath. The other mum was clearly not doing a fantastic job of teaching her kid right from wrong but I suspect I didn't deal with this properly either and probably should have taken it on the chin - both for my own dignity as well as for my son's benefit.
What's the best way of dealing with these kinds of playground situations?