I did three WWOOFs one summer with a girfriend while travelling the US.
The first one was animal husbandry near Missoula, MT. We took care of sheep, goats, and horses, mostly milking, cleaning stables, etc. The work didn't take too long to do as the farm was small, so we spent free time hiking or reading in the cabin we were stayin in. Good experience.
Second farm was in Missisippi. The farm owner, who was cool and knew a lot about wild birds, had let the farm fall to pieces in the blistering summer heat and divorce drama. We tried to save it, under little direction, then left early.
Third farm was a larger (fifteen long raised beds and three greenhouses) vegetable farm near Fayetville, AR. This farm was awesome. We did planting, harvesting, weeding, CSA prep, coop construction, etc.. The farm owners had two kids who liked us and my ex would hang out with. During random times of the day the owner would call "SAFETY MEETING" and all who wished to attend would meet in the bamboo grove and smoke weed. The farm was part of an intentional community with cool people on it, doing projects such as building a steamboat, or building sustainable housing in the surrounding towns.
I would recommend WWOOFing, just be carefull about what farms you choose.