All their friends do it.  They can probably figure out how to do it behind your back.  And, heck, you probably do it.  So how do you keep your kids off Facebook?

More practically speaking: At what age do you let your kids use Facebook?

This is the first of a new occasional series on this blog called Red Tape Parenting Debates. We'll ask some of the basic parenting questions that arise from the clash of children, technology and money.  We'll provide some research and frame the issues, but chiefly we want msnbc.com readers to share their experiences and help each other with some of the most vexing issues facing parents today. There are no right answers, but there might be a better way.  If you think you have one, share it; if you're unsure about your strategy, read on.

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Ongoing series: Red Tape Parenting Debates
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Facebook and age has been in the news a lot lately. To set the stage, let's clear up U.S. law on the matter. The Child Online Privacy Protection Act does not bar children under 13 from using websites, nor does it prevent companies from working with kids. It bans the collection of personal information contributed by kids under 13 unless the website gets "verifiable parental consent."  The "verifiable" part can vary, but generally involves getting something like a credit card number from a parent as proof of age.

This law, however, hasn't stopped kids from signing up for Facebook — and it might be the most violated law ever. A Pew Internet & American Life Project survey recently found that  46 percent of 12-year-olds use social networks.  A Consumer Reports study found more than 5 million U.S. children under 10 use Facebook.

Facebook does nothing to keep young children off the site; it relies on parents to do that. In a meaningless gesture, it doesn't allow kids who declare themselves under 13 to register.  But simply trying again and declaring a legal age circumvents the token age restriction. 

Recently, Facebook CEO Mark Zuckerberg told an education conference that elementary school children would benefit from social networks and that his firm would work to remove age restrictions, according to Fortune.

"That will be a fight we take on at some point," he said, though he backed off those comments later.

The clear reality is that young kids use social networks today.  In fact, 17 percent of parents recently said they were OK with pre-teens on Facebook, up from 8 percent one year ago. That study even hinted that some parents help their kids lie to get onto the site.

Whatever the law,  parents, children and Facebook have together made up their own rules about kids and social networks. That's not necessarily a bad thing -- but it is bad if this change is happening without healthy discussion and debate. I hope we can have some on this blog.

There's nothing magical about passing your 13th birthday. It's just as easy to imagine a mature 12-year-old who's ready for Facebook as it is to conjure up a 14-year-old who shouldn't be on the site.  What's important is that parents make a conscious decision about when Facebook use is appropriate, and not simply let the cart pull the horse. 

There are risks to early Facebook use.  Many are obvious: Sexual predators lurk on the Web, and Facebook could be a place where they find targets. Cyberbullying is even a bigger risk, as young children often don't have the emotional and psychological awareness to make good decisions about what they post.  Many parents are also horrified when they stumble on pictures posted by their kids' friends acting out during early stages of puberty.

In a more fundamental way, Facebook and other similar technologies might be rewiring the way kids' brains work, some scientists have warned.  There's no conclusive research, but people like British neuroscientist Susan Greenfield have spoken out warning that "screen relationships" are bad for developing brains.

These dramatic concerns can seem distant and unlikely, however, and most parents will find the Facebook discussion involves more mundane problems, such as whether their kids are glued to social networking sites instead of doing their homework. Are they up late chatting with friends instead of getting enough sleep?  Are they sitting in front of a computer on sunny days when they should be exercising outside?  And perhaps most of all, is Facebook use triggering one of those constant power struggles between kids and parents that the adults are doomed to lose? After all, saying no at home probably means the kid will do it anyway at a friend’s house, or with a smart phone under the covers late at night.

Naturally, Facebook offers many benefits -- otherwise 750 million people wouldn't be hooked on it.  But clearly, there is an age where kids are too young to use it. Congress, albeit awkwardly, has decided that age is 13.  What is your age? And if you let your under-13 kids use Facebook, do you place restrictions on them to moderate the experience? For example, do you manually approve all their new friends?  Do you know their password and check on their account? Do you limit their time using the site? Tell us below.

RED TAPE TIP: There are Facebook alternatives designed for under 12 kids. Most limit interactions, and make strong efforts to verify parental permission. Of course, none offers the free-flowing communication that makes Facebook so attractive. Mashable recently reviewed five such sites.

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