Custody schedule for summer break

Trying to figure out what's fair for summer since both me and my ex want to spend quality time with the kids. Our normal schedule is 50/50 but summer is different. She wants them for 4 weeks straight, I want to alternate weeks. The kids are 7, 9, and 11 so they're at an age where they have friends they don't want to leave for too long. What do you guys do? How do you make it work?