I have a friend who's son has a mid December birthday and I have 2 granson's with December birthdays. My friends son has his birthday party in January when they come back from Christmas Break. He just gives everyone their "hold the date" cards before they go on break then sends out the invites as soon as they come back.
My oldest grandson is 14 11/12 and he only wants to get together with his closest friends and hang out, pizza party with a bunch of video games or some new movie on the big TV.
The grandson that is younger and has a December birthday always has his party near his date. It's at the beginning of the month so that does make it easier.
We're thinking about the venue already. We'll do it inside and on a Saturday. Full class invited.