do you invite her in for a cup of tea (even if you've never really met) or do you simply return her dc? I'm just starting out with playdates for dd1 who is in reception and wondered what the "done" thing is. On one hand I'd like to invite the mothers in for a cup of tea to get to know them. On the other, I've usually just got in from work and it is the dcs bedtime. I don't want to be seen to be rushing the friend/mother off if the usual thing to do is invite them to stay for a chat at pick-up time.
Depends how well I know them, but usually do invite them in for a cup of tea/glass of wine and hope they say no! I'm generally a bit knackered by then and just want to get on with getting my own children bathed/ready for bed and collapsing on the sofa. I'm probably a lightweight though. I quite often take the child home afterwards rather than have their mother collect, because we live further away from school than most of their friends.
Invite in for a cup of tea on the first one or two occasions. Because, yes, it is nice to know the parents of the children your dc play with at school. You don't have to do it every time they play together.
Arrange an earlier pick up so you have time for tea. Drop into conversation when arranging pick up time that your DC's bedtime routine starts at x time so the parent understands why you'd like their DC to be picked up at a particular time.