Perfect Chemistry (Perfect Chemistry Series #1) by Simone Elkeles

Opposites attract when a good girl with a ""perfect"" life meets a bad boy with nothing to lose in this New York Times bestselling steamy romance. When Brittany Ellis walks into chemistry class on the first day of senior year, she has no clue that her carefully created ""perfect"" life is about to unravel before her eyes. She's forced to be lab partners with Alex Fuentes, a gang member from the other side of town, and he is about to threaten everything she's worked so hard for-her flawless reputation, her relationship with her boyfriend, and the secret that her home life is anything but perfect. Alex is a bad boy and he knows it. So when he makes a bet with his friends to lure Brittany into his life, he thinks nothing of it. But soon Alex realizes Brittany is a real person with real problems, and suddenly the bet he made in arrogance turns into something much more. Neither Brittany nor Alex is prepared for the most surprising chemical reaction of all- love.