Wes: Privacy. Respecting it used to mean deciding whether to read your teenager’s diary or look under his bed. In the last few years it means deciding whether to snoop on e-mail, text-messaging and Facebook, so I’ve evolved a few core principles for where the limits should be:

• Age. As teens age toward 18, they should be given more responsibility for driving, self-regulation, etc. The same is true for privacy, assuming that he or she is showing a normal level of maturity. Unfortunately, at that same time they’re increasingly exposed to things that aren’t good for them and often create conversations and postings that can come back to bite them.

We discussed this in our January columns on sexting. So, while this is generally a good rule, it won’t always hold, which brings us to the next one.

• Probable cause. Under the Constitution we have a right to be free of unreasonable search and seizure, which can only be limited if law enforcement has evidence we’ve committed a crime.

The same should apply for teens in the home. Parents should grant reasonable privacy until they have cause to do otherwise. Once that level of suspicion is justified, privacy must be earned back.

• Some things just aren’t private. As I said a year or two ago, the words “Facebook” and “private” should never be used in the same sentence. If it’s appropriate to share with the world, it’s fair game for parents. Text messages and e-mail are a little trickier, since they can be forwarded easily and create all sorts of trouble, but until probable cause is reached, they should be considered private property. Photos on phones or computers should either be encrypted so no one can see them without the code, or just as accessible to parents as they are anyone else.

Back in the old days diaries had locks. Modern technology can have them, too, and teens should give that some thought before sharing their innermost secrets in any electronic format.

• Emergency backup. Recently a parent told me she keeps all her son’s passwords in a sealed envelope, so that in the event of an emergency, or if probable cause is reached, she can access his accounts. I say that as long as the parent can use this power ethically, it’s a great idea.

Ben: We all know nice people who mean no harm but can’t keep a secret to save their lives. The Internet is like these loose-lipped friends, except it’s more of a loose-lipped Godzilla.

Think about the Internet long enough, and you’re bound to get a little creeped out. We’re talking millions of people swarming all over Facebook, MySpace and YouTube on a daily basis with little accountability. Have you ever thought about how many times you’ve been Facebook stalked? We’d like to think that it’s only our attractive classmates being drawn to our profile, but how would you know? Employers, college admissions workers, sexual predators, grandparents are all checking our pages. So, here’s my list of guidelines:

• Watch what you put up. You don’t want creeps getting a hold of your address, and you don’t want your boss checking out pictures of the party you were at on your “sick day.”

• Know who can see you. Don’t friend people you don’t know, and don’t leave up your profile for everyone in the world to see.

• Think before you post. Even if only your friends can see what you’re saying, would you shout a secret to all your friends? Don’t say things online that you’re regret in real life later on.

In short, save your private life for real life.

Next week: My son doesn’t want to drive.