Staying Fat for Sarah Byrnes Author: Chris Crutcher. Publisher: Greenwillow Books. Pages: 216. Price: $14.

How far would you go for your best friend? Would you risk your life?

This kind of unselfish friendship exists between Eric Calhoune and Sarah Byrnes in Staying Fat for Sarah Byrnes, by Chris Crutcher.

Eric, an 18-year-old high school distance swimmer, is kind, caring and willing to do anything for his friends and family. Eric's nickname, Moby, (after Moby Dick, the whale) comes from his overweight appearance.

Sarah Byrnes, an 18-year-old with a huge chip on her shoulder, was badly burned as a child and claims that when she was 3, she accidentally dropped a pot of boiling spaghetti on her face and hands, which left horrible burns.

Sarah makes everyone call her "Sarah Byrnes" because she hates waiting for people to figure out the pun between her name and her condition.

Because of teasing by classmates, Eric and Sarah Byrnes develop a special friendship. At first they become friends because she is as ugly as he is fat. But over the years, they appreciate each other for what they are instead of what others think of them.

The test of their friendship comes when Eric risks his life to save Sarah.

Staying Fat broaches many subjects, including suicide, abortion, religion and prejudice, but the main theme is friendship.

Crutcher designed the book so that the different issues, like suicide and religion, come together in the classroom. The students express their beliefs and learn how to respect others'. The book forces you to think about other people's ideas on these issues.

Crutcher also developes characters who are realistic, everyday teen-agers and uses them to teach teen readers that issues like abortion and suicide will at some time touch their lives. This is the strength of this book.

(ZZCPYRT)