Dark Star — R.T. Martin

What happens when the seemingly perfect new girl isn't so perfect after all? A group of high school students take an extra-credit field trip to the bluffs to watch a midnight meteor shower. However, it quickly becomes dangerous when the new girl sets her sinister plan into motion. Perfect grades can't hide her true intentions. As the countdown to midnight begins, students start disappearing. Suddenly, passing science class is the last thing on everyone's mind. How will they all make it out alive? And who is this mysterious new student?