Betsy Was a Junior

Blurb

Betsy Was a Junior is the seventh volume in the Betsy-Tacy series by Maud Hart Lovelace. The story spans the title character's junior, or eleventh grade, year in high school.
The novel begins with the return of Betsy's childhood friend Thelma Muller, who had been living in Milwaukee, Wisconsin since her parents were independent and they wanted to return to their old life, and the departure of Betsy's older sister, Julia, for college at the University of Minnesota. Julia's desire to bypass college and begin a musical career cause her to be relatively uninterested in classes and to focus instead on her desire to join a sorority. Excited by her sister's stories of college life, Betsy and her friends Tacy and Tib join with five other girls in establishing a local sorority at the high school level.
Over time, Betsy finds that the social whirl of the sorority distracts her from her studies and also eventually causes a backlash of resentment among the rest of the student body, which leads to her group's being excluded from their usual leading role in school activities. Moreover, the exclusiveness of the sorority concept pushes away others she would like to welcome into her social circle.