This site is what you are looking for: a treasure trove of books and articles.
This site from Jostens Yearbooks is good.
This site from Taylor Publishing covers lots of good stuff, including themes and a design gallery.
This site from Walworth Yearbooks is also good.
Another site from Jostens.
Look here for a site for high school students. It contains tips on sportswriting, column writing, editing, photojournalism (which talks about photo stories, a good way to cover events for a yearbook. The Life Formula, for example, would be a way to tell a story about an event or happening visually. Take homecoming, for example, or the Strawberry Festival, and think about a photo story: opener, overview, detail, action, interaction, closer.
Tips on here for nonverbals. This site talks about how to observe and show the readers rather than tell them. This is the type of copy the yearbook should contain -- magical moments to recall the good and bad times of high school.
The Creative Process This site could be a good way to get kids to think creatively. Write and think out of the box, not "the way we've always done it."
Cliches can kill good copy. This site tells us how to avoid cliches. Kids often don't know what cliches are; thus, how can they avoid them? It's a fun read.
This site gives 30 tools for better writing. That can mean better yearbook copy.
This site will prepare your students to write accurate and complete cutlines (or captions) about who, what, when, where in the photograph.
This site (although it is for newspaper, it can still be used for yearbooks) tells how to set up a stylebook. This gives students a way of knowing what type to use, what size, what weight, etc., Thus, the headline type, the cutline type, the copy type will be consistent and students can refer to the stylebook to find answers to their questions.
This site gives a lot of tips. One on interviewing will make the students understand how important it is to gather information from sources. How to ask questions and what to look for in an interview.
This site is for LifeTouch Yearbooks.

Critiques available. E-mail Chet Hunt at  cfhunt@gmail.com