It seems as if all these beaches are our favorite, but Cala Llonga is one of the best for kids. It is a horseshoe shaped beach with two large resorts in both sides.
As for location, you can see on the map where it is exactly.
Several restaurants and pubs in walking distance, plenty of self-catering apartments and the Sirenis Cala Llonga Resort is the all-inclusive hotel up on the left which has a lot of great family friendly-activities including kids clubs, shows, etc Like the Iberostar hotels we stayed at in the Dominican Republic only with the space the pool is not the amazing pools you have in the DR. Anyway, I would LOVE to stay there with the kids. I think the other on the opposite side is a Palladium and is an adults-only resort – it was at one time.
We probably have a connection here as this was the first location in Ibiza I stayed like 13 years ago!