Talking about their general classmates.
I used to spend roughly the equivalent of what they'd spent on inviting my child to the party, eg. for a soft play party I'd spend around £10.
Then my DC had a soft party and I couldn't believe the cheap tat some parents gifted! Have been unsure of etiquette ever since. I am constantly working to a budget so don't want to overspend, but I'm also curious what's the norm 