Jessica would stop at nothing . . .

Beautiful and ruthless, Jessica Wakefield is determined to be chosen queen of the fall dance at Sweet Valley High. If she can win the contest, she's sure to win Bruce Patman, the most sought-after boy in school.
The only person standing in her way is is Enid Rollins. When she discover the truth about Enid's past, she knows the crwon is within her grasp. She don't care the Enid is her twin sister, Elizabeth's best friend - or that revealing the secret may cost Enid both her reputation and the boy she loves . . .
Only Elizabeth can save Enid from Jessica's vicious gossip - but can she stop her scheming twin in time?

Excerpt:

It wasn't fair, Jessica raged, tears streaming down her face. Enid was going to the fall dance with Ronnie, and she was sure to be named queen. Ronnie was so blind with love that he'd swing a million votes her way.
Jessica sighed. she just had to win. If she were queen, Bruce Patman would finally notice her. She'd never wanted anything so badly in her entire life. She'd do anything to make it happen.
Out of the corner of one wet eye, Jessica glimpsed a piece of paper sticking out from under the bed. It looked like a letter.
"Dear Enid," she read with sudden voracious intrest. A smile crept slowly across her features as a plan shaped itself in her mind.

WELCOME TO SWEET VALLEY HIGH — a world of good girls with big secrets, bad girls with no remorse, rich boys in stunning tuxedos, and shimmering California sunsets.

Jessica Wakefield only wants two things: to be chosen homecoming queen, and to dance in the spotlight with Bruce Patman. But there’s one girl standing in her way—Enid Rollins, her twin sister Elizabeth’s best friend.
When Jessica discovers Enid’s deepest, darkest secret, she has a choice to make: be nice and keep quiet, or reveal it to the entire school and clinch the crown for herself.
The queen will be breathtaking. But the quest for royalty is never pretty

Can Jessica play Bruce Patman's game and win? Playing with Fire