gang violence (like how they see it..maybe theyre misunderstood)
cliques( how the actions of girls in middle/high school affect a single girl)
love( a love story is always good)
the end of the world(write about a charactar going through the apocolypse)
write your novel in first person. it is always more personal and makes the novel more pleasant to read. try to use lots of literary devices and use detail. play with the reader's emotions and get them really attatched to the main charactar