If you like The Midinghters by Scott Westerfeld, you may like these titles. If you haven’t read the rest of the books in the trilogy, you’ll definitely want to start there (Touching Darkness is #2 and Blue Noon is #3). Here are some other books with magical aspects and teens doing cool things:
The Supernaturalist- by Eoin Colfer.
In futuristic Satellite City, fourteen-year-old Cosmo Hill escapes from his abusive orphanage and teams up with three other people who share his unusual ability to see supernatural creatures, and together they determine the nature and purpose of the swarming blue Parasites that are invisible to most humans.
Inkheart -by Cornelia Funke.
Twelve-year-old Meggie learns that her father, who repairs and binds books for a living, can "read" fictional characters to life when one of those characters abducts them and tries to force him into service.
A Great and Terrible Beauty -by Libba Bray.
After the suspicious death of her mother in 1895, sixteen-year-old Gemma returns to England, after many years in India, to attend a finishing school where she becomes aware of her magical powers and ability to see into the spirit world. If you like this one, it is part of a series - #2 is Rebel Angels and #3 is The Sweet Far Thing.
The Haunting of Alaizabel Cray -by Chris Wooding.
As Thaniel, a wych-hunter, and Cathaline, his friend and mentor, try to rid the alleys of London's Old Quarter of the terrible creatures that infest them, their lives become entwined with that of a woman who may be either mad or possessed. (I also loved, Poison, by Wooding!)
Uglies- by Scott Westerfeld.
Everybody gets to be supermodel gorgeous. What could be wrong with that? Tally is about to turn sixteen, and she can't wait. Not for her license-- for turning pretty. Another trilogy--#2 Pretties, #3 Specials.
Betwixt- by Tara Bray Smith
Three alienated teenagers are drawn to a strange outdoor concert in the woods outside of Seattle, where they discover that they possess magical powers and that their destinies are intertwined.
Wicked Lovely- by Melissa Marr
Seventeen-year-old Aislinn, who has the rare ability to see faeries, is drawn against her will into a centuries-old battle between the Summer King and the Winter Queen, and the survival of her life, her love, and summer all hang in the balance.