I'm starting to do some research for my oldest daughter's literature curriculum. I plan on using a combination of short stories from a literature book and book units. I've found that there are several sites with free units for high schoolers. Here they are...
Harper Collins Teaching Guides
Penguin Teaching Guides
Glencoe Teaching Guides
Emily Dickinson: There are a few questions, links to the particular poems (which you can print) and then discuss.
Random House has a few, but not many that I'm interested. I did find this one on The Lord of the Rings Trilogy... you can find it HERE.
A Wrinkle in Time guide links on the author's site. (6th grade book), but I noticed that many sites use middle school books in high school as well.