Maybe skip the bobbing for apples activity, but otherwise I would just keep an eye on things. If they’re still at school, then they’re plenty exposed there — so is a birthday party going to make the difference?

Our daughters’ birthdays are coming up as well, and for now I’m keeping the plans, but am at least preparing in case schools cancel, etc.

FWIW, in response to the other reply, as a parent of 3 children under 6, I can say with recent experience that a birthday can be very important to a three year old (depending on the kid obviously).