Back to school means back to coping with cliquish girls, some moms report indignantly on Facebook.

Exclusion can start as young as preschool. From using birthday parties as bargaining chips to refusing to play with a classmate outside, girls start testing their social power even before they turn 4, research into the social nature of children shows.

Ten years ago, I wrote in this column about the books of two young women, Rosalind Wiseman and Rachel Simmons, whose early work aimed to uncover the hidden culture of mean-girl behavior and find solutions. Since then, the two authors, who often appear as specialists on TV and in magazines, have continued to try to empower girls to talk about their experiences and stay strong – particularly in the new world of cyberbullying.

As girls’ social testing gains momentum, the tactics can range from subtle flips of the hair to nasty gossip to physical aggression. What drives parents crazy: Two girls are best friends, one dumps the other, then they’re best friends again. All within a week.

“If you went through this as a child, it will push your buttons,” says Wiseman, author of “Queen Bees and Wannabes.” “Admit to yourself: ‘I can’t stand these kids.’ But don’t say that to your daughter.”

Wiseman encourages “checking your baggage” – being aware of your own experiences and their impact on how you parent your daughter as she deals with common social conflicts. Process your own childhood memories, whether as the victim or the aggressor, and then discuss them with your daughter to help her gain perspective.

Wiseman says she revised the 2002 version of her “Queen Bees” book in 2009 partly to help parents feel less overwhelmed by technology and more empowered. Her colleague Simmons did likewise, writing “Odd Girl Out” in 2003 and revising it in 2011 with new material on cyberbullying.

Simmons’ goal with the revision was to help girls and their parents handle the dangers of life online. Social exclusion takes on a whole new momentum in cyberspace, she says, adding that it’s a common mistake to write off girls’ aggression toward each other as a phase.

“If we don’t help girls identify aggression and understand it is inappropriate, they will learn to be treated this way,” Simmons said nearly 10 years ago. Her philosophy continues to resonate today.

Simmons is the co-founder of the Girls Leadership Institute, which inspires girls to be true to themselves. The group teaches the practices of emotional intelligence, assertive self-expression and healthy relationships, giving girls the skills and confidence to live as leaders.

Girls need help to learn to identify what characteristics they want in a friend, the authors agree. If they take whatever is dished out, the aggressors get away with mean-spirited choices.

Tips for parents

• Be careful what you say: An enemy today may be a friend tomorrow.

• Instead of going into fix-it mode, be a source of comfort. Help your child think through what’s happening, and talk about the qualities she wants in a friend.

• Try to build a foundation at home where your daughter can come to you to share her concerns.

Tips for teacher

Teachers can ward off exclusive behavior problems in classrooms by posting rules in class such as:

• Treat one another with respect.

• Be kind to your classmates.

• No whispering.

• No behavior that excludes other classmates.

• Keep your hands to yourself.

Betsy Flagler is a mother and preschool teacher. Email her at p2ptips@att.net or call 704-236-9510.