Preppy can refer to a conservative, timeless style of dress and the simple choices of classic jewelry that evoke an air of confidence in one's natural beauty. But a true preppy attends a Boarding School. Their parent or parents often attended traditional boarding academies such as Phillips Exeter, Phillips Andover, Deerfield, Hotchkiss, St.Paul's, Groton, St.George's, Choate-Rosemary Hall, Lawrenceville and the like. They grew up knowing this was their likely educational path and never thought it was odd to leave home for High School. They hope to attend an Ivy, Stanford, Cal or one of the monied Northeast private colleges such as Middlebury, Williams, Trinity or Bowdoin etc.
They may have grown up in California but they likely have east coast family ties and live a pretty bicoastal existence once they start "Prep School". They usually play lots of sports and know where the squash courts are as well as what a "shell" is or they are a really accomplished musician. They look out their dorm window and see brick or Gothic stone; as well as Patagonia and North Face clad preps sometimes playing with little "fac brats" on the expansive grassy lawns. They often learn at oval tables rather than at traditional classroom desks. They are often sleep deprived because of the demands of 24/7 dorm-life, sports, clubs and study. They sometimes have to fake sick and go to the Infirmary since that is the only way to skip class and sleep without getting into trouble with warnings like "green cards" or "dickies". They sometimes get "put up" for discipline issues that would just involve being grounded if they lived at home. They sometimes get stressed and burned out and move back home. It's possible to be forced to withdraw from the academy. They often graduate with really tight lifelong friendships and are so loyal to their Alma Mater that when they die they leave generous endowments from their estate to their "Prep School" and hope their grandchildren will attend as legacies and enjoy the benefits of their alumni giving.