The 1974/1975 Growing Up Skipper (Mattel #7259) is a highly sought-after vintage doll, especially when found "New in Box" (NIB). The "Growing" Gimmick: By rotating the doll's left arm counter-clockwise, she grows from a 9.25-inch young girl to a 9.75-inch curvy teenager with developing breasts. This can be reversed by turning the arm clockwise.