Nerd- a girl staying after school gets caught up in an act of vandalism at the school and leaves with the gang who did it, they hold her for ransom in order to have her both work out their operation and fund it.

Sirens- people living after the zombie apocalypse starts, they have sirens to warn them when to go back to their houses, but a girl gets separated from her group when the sirens go off and she has to try and survive

The Way Out- a dystopian novel which I can't think of a good description for