Ten years ago yesterday, our view of the world and our view of sending our children to school changed forever.

It was April 20, 1999, when two troubled teenagers, Eric Harris and Dylan Klebold walked into Columbine High School in Colorado, brutally killing 12 and wounding about two dozen more.

While it wasn’t the first school shooting it was one of the most heart wrenching, in part because of the live media coverage that had the entire nation — and ultimately the world — watching the events unfold.

This tragedy changed us, and even 10 years later the impact can still be felt.

There are still many lessons that we can take away from this.

First, our schools must never take safety and security for granted. Strict measures must be put in place and followed.

Pro-active measures will make the difference and every threat should be considered real. A good example is the recent bomb scare at Fairland High School.

Secondly, parents and educators must always look for warning signs — red flags — that may show that a child has lost his or her way and be in need of professional help. The Virginia Tech tragedy was a key example where the signs were there.

In each of these shootings, teens or young adults had shown signs of violence or anger but these signs were essentially ignored.

Third, we can all be inspired by the stories of the Columbine children who survived this massacre and have moved on with their lives, never letting this tragedy rob them of the ability to live.

Columbine changed us, for better and worse, so it important that we make sure we never forget the lessons learned.