If 15-year-old Hannah Gittleman had it to do all over again, she would have asked more questions when her parents divorced. "Even though I was only 6 years old," she recalls, "there were a lot of things I wanted to know about what was going on.

"But I guess I was too scared or something to ask questions, so I never included myself in things that wound up affecting my life. I just let the grown-ups lead me."

Thirteen-year-old Sarah Steele had feared she would lose touch with her father when he moved out of state following her parents' divorce. "But I found it's not so hard to communicate," she says. "It just takes a little extra work."

This "wisdom of experience" -- passed along by "divorced kids" -- can be "especially helpful advice" to other youngsters whose parents are divorcing, say the two teen-agers.

"The last thing a kid wants to hear when his or her parents are going through a divorce," says Steele, "is some other adult telling you what you should be thinking or feeling. Because when your parents are divorcing your faith in adults is shaken."

"If an adult tells you everything will be okay," adds Gittleman, "you may have doubts. But if a kid who's gone through it tells you what you can expect, I think you're more likely to listen."

This "kids-talking-to-kids" approach is the basis for The Kids' Book of Divorce, (Lewis Publishing Co., 123 pages, $9.95) written by Gittleman, Steele and 18 of their classmates at the innovative Fayerweather Street School in Cambridge, Mass.

Drawn from their own experience and interviews with counselors, judges, other children of divorce and members of the clergy, it presents an honest, appealing kid's-eye view of everything from "weekend Santas" to step-parents.

Teacher Eric Rofes got the idea for the book three years ago, when he started teaching a Fayerweather "unit" -- a mixed-age group of 6th, 7th and 8th graders.

"One boy made a joke in class about not seeing his father very much," recalls Rofes, 26, who is touring the country with Gittleman and Steele to promote the book. "The other kids laughed along with him, but you could hear the seriousness behind the joke. That struck with me."

Over the next few weeks Rofes discovered that 14 of his 20 students had divorced parents and many had unresolved feelings aobut the experience. "Divorce is so much a fact of life for all families today," he notes, "that even kids whose parents are together may fear divorce whenever their parents have a serious fight."

Although Rofes had previously taught in a school where divorce was a forbidden topic, he says, "Fayerweather was different . . . they are committed to addressing the full range of children's needs. Kids speak openly about everything from pimples to family problems."

After talking with school administrators and parents -- some of whom initially feared dredging up painful feelings -- Rofes got approval to begin class discussion groups about divorce.

He asked students to read some books bout divorce written for children -- which he thought were good -- and was surprised to discover that they didn't like them.

"Some of the books had a real bias toward adults," the kids write in their introduction. "Some issues that we thought were very important, like little brothers and sisters, weren't included at all. And some of the adults who wrote these books talked down to kids like we were jerks."

When Rofes asked the students if they wanted to write their own book he got mixed reaction. "I thought it was a little weird at first," admits Steele. "But most of the kids liked the idea, and when we started interviewing people I decided it was pretty neat."

The research, interviewing and writing took a full year. "It was a trip to see two 11-year-olds call up a judge they'd never met," says Rofes, "then go off with a tape recorder on public transportation to interview him."

The hardest part, says Gittleman, "was finding the offices. I got lost some."

Rofes spent the next year sending the manuscript to publishers. "The mainstream publishers wanted us to cut parts," he says, "like living with a gay parent and parents having friends sleep over. We all talked it over and decided we didn't want to cut it."

Since its publication earlier this year, they've gotten nationwide attention -- including inquiries into movie rights. They are currently negotiating paperback rights and plan to split the royalties in 22 equal parts -- for each child, for Rofes and for the school.

"I wanted it all to go to the school since it was a school project," says Rofes, who estimates each share will total between $1,000 and $5,000."But we took a vote and I lost, 17 to 4."

Among the book's best advice for kids, says Steele, "is going to be informed about what's happening with the divorce. Ask questions about whatever you want to know. Remember it's not just your parents splitting up -- it will affect how you live, too.

"If your parents are going through a custody battle, make sure it ends up in a way you feel good about. Tell your parents, even though it's hard, how you want to live."

"Parents," says Gittleman, "should listen to their kids. A lot of times they get so wrapped up in their own emotions that they forget there are other people out there whose lives are involved. Or they just assume the kids want to stay with the mother or figure they know what is best. They ought to ask their kids what they think.

"Also, kids and parents need to know that it isn't their fault. There's guilt on both sides that shouldn't be there. Kids realize that it may be better for parents to split up than to stay together and fight all the time."

One thing many parents don't do, but should, says Steele, "is tell their kids about the divorce as soon as they know. Kids have a right to know what's happening in their lives.

"In a lot of cases parents wait a week or a month to tell kids, but the kids can tell something is wrong. Or one kid is told and asked not to tell the other kids. That's not being honest."

Both parents should tell their kids together, adds Gittleman. "If only one parent is there," she says, "it makes the other parent look like the bad guy."

When parents have someone sleep over, she says, "they don't have to ask your permission, but they should tell you this person may sleep over -- so if you run into them at night you won't get scared. You have a right to know who's sleeping in your house."

The biggest misconception about divorce, Steele says, "is that it will totally mess up the kid's life -- which isn't true. They may temporarily have problems and need to see a counselor which isn't so bad. But when people talk about this 'broken home' stuff it makes me want to say, 'Go away!'"

Both girls -- and their co-authors -- agree that divorce isn't easy. "But there will come a day when things will settle down," they write, "when you will be able to look back without the intense pain you felt earlier.

"While divorce never ends, it grows easier to live with until you learn to fully accept the fact that, for better or worse, you have lived through one of the hardest times any child has to experience. And all of us feel stronger when it's finally a part of our past."