I can't speak highly enough of the editor and writers at Student Filmmakers magazine. They produce a magazine that is loaded with a wide range of articles covering every discipline within the filmmaking process. The writing is directed at high school and college readers and features a clear succint style. Recent contributers have included John Badham (War Games), who wrote an article on directing actors.When the magazine launched they allowed students to sign up for free subscriptions. While they have currently discontinued that offer, teachers can order free class sets. That's right, order a box filled with 100, or whatever you need, delivered for free every month. This offer is open to both high schools and colleges in the U.S.To obtain free bulk distribution of magazine for your classroom you need to fax or mail in an application. You can find the instructions at this link.
Update: It appears that they have taken down the free bulk distribution offer.
See the Video Instructor list of free industry magazines.