Depends on the age. If the party has legally aged people who can drink, I suggest it be in an enclosed place, and a place where people can leave their keys and not drive. Make sure there is plenty of coffee for after. And if someone has had to much that they make plans to stay overnight. If this party is not of legal age, it should be supervised by an adult. I think beach parties are fun, dance parties, picnics, there is a lot to do outdoors. And it is healthy to breathe fresh air.
One good idea is to go dancing with friends at a club and enjoying yourselves. Other good ideas include having a beach birthday, inviting friends over at home and cooking special dishes or getting a particular joint, like McDonalds to arrange a nice birthday party for you.