Summer Madness by Janet Lambert (1962)

Ginger Johnston, finishing her junior year at high school, is uneasy about the coming summer. Her main problem, or at least so Ginger thinks, is the change that she is convinced will have undoubtedly have taken place in Spark Plug Blake, the "boy next door," pal and now, college man. The last description of Spark Plug worries Ginger most. She has overheard conversations between her mother and Mrs. Blake that indicate that Spark Plug worries Ginger most. She has overheard conversations between her mother and Mrs. Blake that indicate that Spark Plug is romantically interested in a college classmate and has invited her to visit him during the vacation. Ginger decides that the only course of action against this unknown and sophisticated girl is unobtrusive, but constant attendance to Spark Plug throughout the summer.

While Ginger is working out the details of her campaign, her parents have also been struggling over a decision about the future that will change Ginger's plans, not only for the summer, but for a long time to come. Mr. Johnston is going to take a job in another city, and the family will have to move there.

This is the situation in which Ginger finds herself. Pulled between her loyalty and love for her parents and her devotion to Spark Plug, the emotional adjustment she is asked to make proves to be the biggest she has yet had to face. What is Ginger to do about Spark Plug, about her friends, about her whole way of life if her parents move away from Cheltham.

Janet Lambert, as always, writes with a sharp insight into the continually changing world of teen-agers and with a sympathetic understanding of the problems that young people must work out for themselves. (from the inside flap)