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Your kid is starting to outsmart you. Here's how you can move beyond "because I told you so," acknowledge their reasoning skills, and even let them win. - Parenting.com

When teachers at Baylee McGinnis's Charleston, SC, school banned ball playing during recess, the 9-year-old told her mom, Kristy, her idea for a protest: get all the third-graders to line up and yell "Balls! Balls! Balls!"
Funny, but maybe not the best strategy. Instead, Kristy persuaded her to write a letter to the principal. So Baylee did -- and convinced her to allow balls at recess again. Success!
Tweens are more likely to protest what they see as injustice because they have a better sense of what's fair. "Younger kids tend to think whatever adults say is sacrosanct," says Myrna Shure, Ph.D., author of Thinking Parent, Thinking Child. Tweens who question authority are starting to develop values.
You can help kids learn to protest effectively and respectfully by encouraging them to:
See through others' eyes. Help them think about the reasons behind the rule.
Problem-solve. Suggest they come up with a realistic, concrete plan that would address the rule makers' concerns.
Learn perspective. If they want to protest everything, help them set priorities. Ask, "How important would you rate this problem, from one to ten?" Knowing that they can choose their battles will also help them feel more in control.