Mark Sims and Nicole Collier watched their son become nervous during eight years of custody battles. Isaac, now 10, seemed fearful and took to biting his nails.

Then the two separated parents took a six-week class geared toward separated or divorced parents, and everything changed. In the court-ordered class, they learned how to put their anger aside and focus on what was best for their child.

Both have seen the difference in their son.

“Since we have resolved our issues, he has really relaxed and is much better for it,” said Collier, 37, a stay-at-home mother in Los Angeles with four other children.

The class, aimed at teaching parents to continue parenting together after their marriage or relationship has ended, is part of a changing approach to helping families through a divorce or separation. Such parenting programs are now required in 27 states. In other states, judges can order parents to attend, or there are districtwide or citywide mandates regarding such programs, according to a 2008 survey of mandatory parent education.

“Divorce is so common today, people forget it’s still emotionally complicated or emotionally devastating,” said Robert Emery, director of the Center for Children, Families and the Law at the University of Virginia. To counteract this, Emery said divorce-related parenting classes take a “child-focused, parent-friendly approach” to helping parents work out a parenting plan.

The classes reflect how dramatically family law and policy has changed in the past decades. Gone are the days when divorce proceedings focused on the division of the couple’s financial assets.

“Children’s issues were not as prevalent in the 1960s and the early 1970s,” said Peter Salem, who is executive director of the Association of Family and Conciliation Courts in Madison, Wis. “There was a pretty straightforward way of doing things. Mom got the kids, dad visited every other weekend, and that was that.”

Now, there’s a strong focus on the emotional health of both parents and children.

“One of the biggest things that happened to us in the class, and it’s the simplest thing, is to have courtesy when you talk to the other person – to say stuff like ‘thank you,’” said Sims, a 48-year-old Los Angeles musician. “It seems like a really simple thing, but it changes your attitude about what you’re doing.”

The parenting classes vary greatly. There are lecture programs, small groups, and a growing number of Internet-based classes that can be used to fulfill court orders for parent education.

The goal of most is to help parents understand the emotions that go along with divorce, and separate their parental relationship – which will continue – from the adult relationship that is ending, said Salem.

There are other common themes. Among them: Children shouldn’t take on adult roles when the adults are struggling.

“They shouldn’t be necessarily setting up the cable service, the phone service in the new apartment. That’s not their job,” said Salem. “There are certain household responsibilities, but children still need to be children.”

Another: The child needs both parents in his or her life if possible.

Joan Haynes, a naturopathic physician who took a court-ordered class when she divorced last year, went in thinking it would be a waste of time. But she was surprised by what she heard there.

“They said divorce, per se, didn’t hurt children,” said Haynes, of Boise, Idaho, who now shares custody of her 10-year-old daughter with her ex-husband. “What hurts children is the ugliness around the divorce, or even if the parents are still married, it’s the fighting and putting the child in between.”

According to the Centers for Disease Control and Prevention’s National Vital Statistics Report, the divorce rate reached a high in 1970 and is slowly declining. Some demographers estimate divorce hit a high of 50 percent in 1970, and is now around 43 percent. However, in the same period the number of people having children together without marriage has risen, and their custody battles can end up in court as well.

Research has shown that some parenting programs can prevent future problems, such as more litigation, said Susan L. Pollet, who with Melissa Lombreglia published a paper on parent education programs in the journal Family Court Review. In a survey, the two found that 46 states have parent education programs related to divorce, some mandated, some not.

“All my clients who have gone, they always come back and say, ‘I’m so happy I went to that; I learned a lot,’” said Lynnette Berg Robe, who practices matrimonial law in Studio City, Calif.

Mandatory classes get a bad rap, Robe said, but they get people in the door and listening to the material.

“It’s not that anybody is trying to get them not to get divorced,” she said. “It’s just that if you behave in a certain way, you’ll end up with an unhappy child who will grow up to be an unhappy adult.”

After eight years of battling, Sims noted that he and Collier aren’t friends – just parents. They prefer to communicate through texting. They go to school conferences together, and recently met up for Isaac’s dentist appointment.

“It’s not like this great thing,” he said. “I would rather not talk to her, to be honest. I’m sure she’d rather not talk to me, but we have to do it for our son’s sake. And this class helped us to be cordial to each other.”