Do you have any countries/areas in mind? in the past we have stayed with kids at the Balaia Golf Village Complex in Albuferia, Portugal.
It's about an hours drive from Faro airport. The complex is made up of a mixture of apartments and villas in its own grounds with 2 golf courses attached. There is obviously a lot of villas that are rented out for holiday use but seems to be quite a few that are used by owners each year.
I was really surprised for the price that we paid that we got the high quality we got - the apartment was v clean, the complex itself is set within a pine trees and has 7 pools throughout the complex - think of it more has a housing estate!
Worthwhile if you want to be in the same place as your mates but not in the same accommodation.
Onsite there are also tennis courts, gym and 2 restaurants and the centre of Albuferia is a short bus ride/taxi away.
The main beach is 5-10 mins walk across the road where there is a lovely restaurant both for lunchtime and evening meals.
Not my type of normal holiday at all - only second one I have been on with partners children but one they loved - we took them in 2009 and they went again in 2010 with mum so mustve been good!
We booked apartments through owners direct but there are lots also on holidaylettings or google the complex itself.