Stephanie has just fallen in with the bad crowd at school. When her new slacker friends start dying in horrific “accidents,” Stephanie is only one who thinks there is a connection. She must figure it out before it’s too late, but what if this is all for her own good?

Thanks everyone,
This feedback is super helpful. I will rework it.

Agree with all previous comments.

As Nir pointed out, you don't need to include names. It's more important to give her a defining characteristic. This is usually something that forms the basis for her character arc - if you described her as depressed then by the end of the film she finds happiness.

Imagine someone "figuring out" something on screen. Chances are it would be a very small, very subtle bit of acting. That's it. So make the goal something bigger. As Nir said - it should be to stop the murders but you can suggest that there's a mystery involved - "she must follow the clues to unmask the killer before somebody else dies".

No need to name the MC as it's better to describe her. What's her major flaw?

As DPG pointed out, the inciting incident isn't clear. What one event motivates her to take action?

Lastly, "...must figure it out..." is a weak goal. Wouldn't it be far more compelling to see her stop the murders?

Check out the 'Formula' tab for more information on how to construct a logline.