High Note, Low Note by Anne Emery (1954)

Senior year -- the year of College Boards, of college plans, of scholarship applications.  Jean's last chance to improve her grades, to win recognition at Sherwood High School.  The last year to be with her friends -- especially Jeff, and Kim, and Scotty.  No wonder Jean has trouble keeping her mind on the music scholarship and all her fine beginning-of-the-school-year plans.

Another delightful story about the Burnaby family. (from the back cover)