You might try Diapers for Jessica, which I think was written by Lauren... four years ago? Five? Three? Anyway, the basic premise is a teenage girl rediscovers diapers, wins a competition (she was entered by her sister) and goes to a diaper camp where all the girls wear diapers and are basically supposed to learn how to be empowered members of society in spite of wearing oversized baby diapers... something like that, I think. I don't remember more specific details about the camp element, but before she went to camp, she was babysitting her neighbor's daughter and snitched her diapers for the fun of it before discovering teen-sized baby diapers.