@Mardyface
A friendship group= a group of people who are secure enough in their affection for each other that they can invite new people in sometimes, meet separately sometimes, realise that in jokes etc are not for public places. Really not related to those around them/not in the group as is about friendship within.
A clique: a group of people who try to create closeness by excluding others, some members don't actually enjoy the friendships within but feel safer than if they were excluded, in jokes are used in public as a way of excluding others, is ALL about who isn't in the group and whether you're accepted or not
I understand what a clique is but my point is that all these "school gate mums" posts are based on the thinnest of evidence.
If you actually unpack what has triggered the evidence of "cliques" its always incredibly inconclusive. "She looked straight past me" or "She was talking to another mum and had her back to me." It's the sort of behaviour will people engage in all the time, unconsciously, because they are busy or preoccupied or not feeling themselves or whatever.
But for some reason the sort of behaviour which would be shrugged off in the workplace or at the bus stop takes on this huge almost spiritual significance when its at the "school gate". I'm pretty certain that in 90% of cases these incidents don't even register with the people who are alleged to have done it, they are getting on with their day.
This is a lot of fairly insecure people who subconsciously feel they are "owed" a friendship network when their kids go to school, often because they haven't bothered to keep their old friendship networks up when they had kids, who then get the hump about other people who have more social skills than them. It's jealousy pure and simle.
The solution is to get on with your life, do what you do and develop actual friends with actual shared interests. And stop caring about a bunch of randoms who you happen to cross paths with at school. Chances are they are thinking a lot less about you than you are about them but you certainly won't help your chances of making friends by getting huffy and sulking about perceived sleights all the time.