Geek Drama (Geek Girl #2.5) by Holly Smale

Harriet Manners knows that the hottest observed place on earth is Furnace Creek in Death Valley. She knows that dolphins shed the top layer of their skin every two hours. And she knows just how badly auditions can go, especially when you're a model. But she has no idea how to get herself out of the extreme embarrassment of the school play or what to do when arch-nemesis Alexa decides it's the perfect opportunity to humiliate her.