"Betsy McCall" was produced by the Amercian Character Doll Company in the late 1950's. She was available in 8 inch, 14 inch, and 17 inch sizes. Below are photos of the 14 inch doll wearing the "School Girl" outfit. The jumper, tights, and shoes are original, but the underdress is a replacement. She is also mising her original hat.
Also refer to these great books for more information on American Character "Betsy McCall" dolls as well as other 1950's dolls.
Dolls and Accessories of the 1950's by Dian Zillner
American Character Dolls: Identification
and Value Guide by Judith Izen