As DuthmenSport says try different campgrounds.
I look for campgrounds that do not have a boat ramp, showers, etc., and that have less than 50 sites.
I find going farther away from a large population area makes a difference (partiers here tend to stay about a 2 hour drive from a large town/city).
Try looking for campgrounds frequented by fishermen - those will usually be quieter than elsewhere.
Often there will be several campgrounds in the same area. Try them all. Usually one will be popular with the partiers and another will be more family oriented.
And last, skip the holiday weekends. Those weekends bring out the party attitude. A week or two before or after those weekends will be far more enjoyable and relaxing.