The first day of school at Perry Hall High School in Baltimore County, Md.

Turned tragic when a student opened fire, critically wounding another student in the school cafeteria.

It’s also a way to share photos and updates with loved ones and friends who live far away.

Its up to adults to teach good judgement, to talk about privacy, and show their kids what behavior is appropriate online.

And while were sure your kid is the good kid, a reported one in four teens are being bullied online, and 50 percent of teens are using the Internet to cheat.

More importantly, they need to be aware of what their own kids are doing and that means checking their Facebook page.

As one mom posted to Facebook in the aftermath of the shooting: Parents pay attention to your kids.

First day of school last day of our life is something any teen might post on their Facebook, can hardly be a red flag that the kid was about to go and shoot up the school.

Maybe someone could have prevented todays incident at Perry Hall if they paid closer attention.

Dr Sylvia Rimm, psychologist and director of the Family Achievement Clinic tells Mashable start when kids first get involved in social media.

In early adolescence, kids dont usually mind their parents checking their Facebook pages from time to time.

If parents check without commenting, they can be alerted to any strange people writing inappropriate comments.

Rimm says thats not always easy, especially with older kids: Unfortunately, if kids want to hide their social pages from their parents, they will figure out a way to do that.

One teen raised an important question in her Facebook response to the shooting, regarding Gladdens last day of our life update.

Dr Rimms answer: If and when kids see anything that suggests violence, they should be encouraged to report the problem at school or at home.

Last year Facebook launched a program aimed at helping prevent suicides, letting friends alert Facebook when users express suicidal thoughts.

Common Sense Media offers these tips for talking to teens about Facebook:Talk to your teens about controlling their information.

Activities on Facebook, including the applications teens use and games they play, can be viewed by others.

Facebook Credits is a virtual currency that enables people to purchase items in games and non gaming applications on the Facebook Platform.

Facebooks default settings tend to keep information public until a user makes it private (although Facebook is a little stricter with minors accounts).

Teens also need to be thoughtful about their status updates, wall posts, and comments on friends posts.

The company makes a significant effort to combat bullying and has whole teams dedicated to sorting out reported content such as rude comments, photo tags, and posts.

Model good behavior for your teens, and keep your own digital footprint clean.

Stefanie O'Neill is a fashion journalist based in Hong Kong, China. Stefanie has a passion for fashion stories and loves writing about fashion news and fashion opinions that matters most to its audience. Stefanie spends a lot of time discovering and researching latest fashion industry news stories in order to make sure the latest and greatest stories are brought to you first on Stylerchic.com.