Guest Stars Zuzanna Szadkowski as Dorota Kishlovsky Nicole Fiscella as Isabel Coates Amanda Setton as Penelope Shafai Yin Chang as Nelly Yuki Sebastian Stan as Carter Baizen Jan Maxwell as Headmistress Queller Laura Breckenridge as Rachel Carr Kate French as Elle Beau Gravitte as Mr. Campbell Harmon Walsh as Julian Rawlins Charles Isherwood as Himself Co Starring Whitney Vance as Kelsey Bess Rous as Fiona Carrie Yaeger as Teacher Daryl C. Brown as Maître d' Uncredited Kristen Bell voices Gossip Girl