Playing for Keeps — Francine Pascal

Split personality...
Jessica Wakefield is head over heels in love with handsome A.J. Morgan. She knows he likes her, but Jessica's convinced he'd really fall in love with her if she were studious and reserved, like her twin, Elizabeth. So Jessica sets out to change her personality completely.

But her plans are threatened when she hears about a fashion contest she just knows she could win. How can she compete and still be the shy, sweet girl that A.J. thinks she is? When the contest turns into a battle to keep A.J. as well as a competition for a designer wardrobe, Jessica has to make some difficult decisions. Will the old Jessica reappear -- and risk losing A.J. -- or is the quiet, serious new Jessica here to stay?