Here's one to get you (and your charges) into the spooky October mood, if it isn't happening naturally for you. I'm a Jersey girl by birth, but living in Cali I sometimes lose track of the seasons. Here's one of my favorites for when the leaves start (or should start) falling...
For Tweens and Teens: Coraline by Neil Gaiman
I picked this up a few years ago and LOVED it. I thought it was the best thing I'd read in ages. Deliciously creepy and wonderful. Coraline is a young girl who moves into a new flat with her preoccupied techie parents. She is bored and her Father suggests exploring her new digs. Coraline finds a key and unlocks the door that separates her flat from another apartment. She meets a woman there who looks just like her mother, except for big, black button eyes. The woman says she is Coraline's "Other Mother". Things turn sinister quickly when Coraline realizes her parents have been trapped by the Other Mother, and it is up to her to save them.
I played the audio book (read by the author) for my fifth graders and they LOVED it. It was edgy, spooky, and they clamored for it after we came back from lunch. They were significantly bummed when it was over. An awesome pick for this otherworldly month.