The attacks of September 11, 2001 were the most exhaustively documented news event in history to that point. Few aspects of that morning escaped capture on video; thanks to a French film crew that happened to be documenting firefighters on a nearby city street, there even exists footage of the disaster's opening moments when American Airlines Flight 11, or "the first plane," as we've grown accustomed to calling it, struck the north tower of the World Trade Center at 8:46am.

Those who remember that day missed very little of what happened. Whether we saw it live or saw it later on news programs, we saw it all. The giant black and orange plume of flame and smoke when United 175 hit the south tower. The wriggling silhouettes of people who'd jumped from the flaming top floors, falling to their deaths. The sight, almost beyond comprehension, of the massive columns of the World Trade Center collapsing like giant sand sculptures, simultaneously atomizing and entombing those trapped within.

They were horrible images. They remain horrible in recollection. And that is probably why, in the years since, they have been shown with relative infrequency. We don't want to see them anymore, and we don't feel we need to. With the exceptions of television documentaries, broadcast media have largely avoided inflicting them on us.

One unintended side effect of that quarantine has been the rise of a generation of children who have no visceral understanding of what happened on September 11, 2001, or why discussion of that day darkens their parents' faces.

The students at Penndale Middle School in Lansdale, mostly aged 11-15, were toddlers and preschoolers on the day when America came under attack. Do these students have any memory of the attacks?

"No, they don't," said John Murray, a ninth grade history teacher at the school.

That is why the 9/11 memorial presentation given to Penndale students on Friday afternoon was so extraordinary.

Yes, there was somber and dignified rememberance of the almost 3,000 people who died in New York, Washington, and Pennsylvania that day. We've allowed ourselves to do that on every anniversary since the attacks. As important as that is, however, it was probably not the most crucial part of the program.

As their fellow students narrated, the Penndale student body watched as a curated narrative of the morning of September 11 played out before them.

They were shown what really happened, and few details were spared.

They saw what we saw. They watched the footage of hundreds of lives being snuffed out as the hijacked planes found their targets. They heard the screams and gasps of bystanders. They saw the bloodied and injured limping and being carried away from the scene, covered in concrete dust and God-knows-what else. They listened as air traffic controllers tried in vain to contact United 93, which had crashed into a central Pennsylvania field after its passengers overwhelmed their hijackers.

How many boring assemblies did we sit through as schoolkids, our eyes on the clock over the door, our minds on dismissal, while our well-meaning teachers and principals droned on from a lectern about some observance that they insisted was important? How many of those presentations do we remember?

The Penndale students will remember this one.

When the presentation first got underway, they behaved like any normal group of hundreds of tweens and adolescents might be expected to behave. They were full of chatter, laughter, and eagerness to get out into the beautiful late summer afternoon beyond the school walls. They raucously cheered popular classmates as they appeared at the microphone.

Then the images began to parade across the big screens behind the stage. Gradually, the laughter and the chatter stopped. They were riveted. Just like we were, ten years ago. They started to get it.

There were, in the Penndale auditorium, fresh gasps. Young eyes fixated on the screen, mouths slightly agape. Innocence lost? Some, probably, yes. But in exchange, understanding. The sort of understanding that we too often shy away from ourselves, much less visit upon our children.

"Thank you for recognizing that history needs to be told," said Joseph Lutrario, a retired New York policeman who was trapped in the debris following the collapse of the towers.

He's right, it does need to be told. Or, better still, shown. It was a gutsy call by the teachers and administrators who designed and approved the assembly, and they are to be applauded. Nobody would have faulted them if they'd delivered a September 11 memorial program comprised exclusively of poignant, soft-edged sentiment.

But we've entrusted our teachers with the mission of helping us educate our children about the world we live in, and on Friday it was a mission the Penndale faculty accomplished with great power and efficiency.