Now maybe I should have been thicker-skinned but the fact that I remember this now (and my memory is pretty dire), says something about how upsetting it felt to be left out.
It wasn't just the day said classmate handed out the invitations which made me feel low either – the others were talking about it before and after. And on the Saturday afternoon in question, I knew the rest of them were giggling together, tucking into jelly and ice cream and playing musical chairs, whilst I sat at home, with only a Girls' World and Sindy doll for company.
So 30 years on, I'm particularly conscious of the politics of kids' party invitations. Get it wrong and you and your child can be 'playground pariahs', or, worse really, leave another child feeling how I did.
But knowing who to invite, when it's not always practical to ask the whole class, isn't always easy.
It's a numbers game
The potential for upset depends, in part, on how many of the class you're inviting and crucially, what proportion you leave out.
If you ask just a handful, you're probably okay (but see below), and equally if you have the cash, energy and space to invite all 30 (or however many are in your child's class), that's fine too. Anywhere in between and you're into potentially tricky territory.
One dad I know – who also experienced 'you're not on the list' disappointments as a child - reckons "leaving out anything less than half is asking for trouble – you've got to ask all of them or no more than 50%."
Another friend, a veteran party thrower as the mother of four school-age children, advises: "About a third or more is an acceptable number to miss off. No fewer."
What's clear is that it's not okay to exclude a very tiny number - the smaller the percentage you leave out, the meaner it becomes.
Separating the girls from the boys
A common approach is to just invite the girls/ boys only. This can work well in some classes but in others where friendships are more gender-mixed, or there's a tomboy or the boy equivalent, it doesn't always solve the problem.
Emma, mother of two girls, one of whom has close friends who are boys says: "With my older daughter we've always invited all the girls in the class only but this doesn't work with my younger one now. If I did that, her two best friends who are boys, wouldn't be there!"
She gets over this by inviting all the girls plus the two boys her daughter plays with, which leaves the vast majority of boys out rather than just a few, something which seems to work well.
'But mum I really don't want X to come!'
What about the child yours really doesn't want to invite but you think they should?
On the one hand it is their party and they need to feel happy and comfortable, but on the other, it means excluding someone.
"I've had one or two situations where the children didn't want to invite someone and I have over-ruled them - I can't support them doing that even if it is their party not mine. I've explained why and they have accepted it," says Rachel, who has a son and two daughters.
Another mum, Amy, dealt with a less clear cut scenario: "In reception there was a child who regularly hit and bit others. I agonised over what to do about my son's birthday party - we wanted to invite the whole class but worried about him starting on the others.
"It wasn't just playground gossip - he was doing this at every party. In the end I asked this boy's mum if she or her husband could stay - I didn't spell out why, as that was awkward - but they were fine about it and kept a close eye on him."
So can it ever be right to exclude a child?
Yes, argues Vicky, mum of one. "It's not the way I'd do it in an ideal world but we have had a situation where a girl was bullying my daughter badly and having her there would have spoilt the party for my child. I wasn't going to allow that and we made a decision not to invite her. The other mother wasn't too happy with me but I reckon she knew the reason."
Ultimately, it comes down to the reason why your child doesn't want the other one there and you can only do your best to work that out and whether it's valid.
'Can his younger sister come along too?'
Always a headache – another parent thanks you for Little Jonny's invitation and then adds a casual "oh and is it okay if I drop Olivia [his 'lively' toddler sister] off too?"
Now the parent might think it's only one little extra but if several parents do it, your barely-manageable-already full class party for 30, can head towards 35 or even 40.
To be fair, if invited children are younger and still at the stage where they need a parent to stay with them throughout, there might not be anyone to leave siblings elsewhere with, so you need to be sympathetic, and allow for a few extras in your planning. If it's a soft play party or somewhere you're charged per child, it doesn't seem unreasonable to ask the parent to pay for the extra one.
But where it's a 'dropping-off' party and you feel others are using your do as free childcare, so they can pop to the shops or out for a quiet coffee, stand firm and just say no! It's a party not a creche!
If you feel awkward, mumble something about numbers being limited and "we really don't think we can squeeze the extras round the table".
This only works though if the other parents actually bother checking in advance, rather than turning up with a full brood on the day - as has happened to Liz.
"They arrive with a sort of cheery 'oh look here's the brother/sister you don't mind?' type of thing. Oh yes sure not a problem here at the soft play where they'll charge me an extra tenner per unexpected child."
I know parents who try and fend this issue off by putting 'sorry no siblings' on the invitations but frankly some folk are rude enough not to care, so all you can do is keep fingers crossed and a spare party bag or two just in case.
Dishing out the invitations
Even if you've stuck with the not-leaving-a-minority-out rule-of-thumb, try and be sensitive in the way invitations are distributed – children gaily waving theirs about at the school gate can truly rub it in for non-invitees.
One option is to ask the teacher if she/you/your child can put them into trays in class (although to be fair teachers are busy and might not have the time). Bear in mind though that with this route, the odd one might not make it home, leaving said children, or more likely their parents, giving you the evils because they think their offspring aren't on the list. It's worth sending a quick follow-up email from any invitee's parents you haven't heard from after a week or so.
If yours is the uninvited, disappointed child
Your son or daughter will have to get used to not being invited to every party - it gets more common through primary school as birthday dos tend to get smaller. Remind them that maybe they aren't great friends with the birthday child and that they have had an invitation to Y and Z's party and that people do have to pick their closest friends, as they will probably do when it's their turn.
Sometimes there might not be much logic to who got invited and who didn't – maybe they'd had a temporary fall out with the child the day they did their party list, or they have drifted apart and yours hasn't registered this yet (it happens!) I know it's hard but try not to over analyse.
Less straightforward, is if the birthday kid is someone they thought they were good friends with. If this is the case, all you can do is offer a sympathetic ear, give them a hug and try and deflect their attention with an appealing alternative plan on the day.
Liat Hughes Joshi is author of Raising Children: The Primary Years.
More on Parentdish: Invite the whole class to my child's birthday party? No way!
PLEASE can you reply to my child's birthday invitations