HALTERN-AM-SEE, Germany -- The Germanwings Flight 9525 crash has been a national tragedy for Germany. The nation is believed to have lost 67 of its citizens, and staff of the budget airline and its parent company Lufthansa around the world observed a minute of silence Wednesday in their honor.

A shocking 18 of the victims came from one high school in the small town of Haltern-am-See. They were flying home to their families after participating in a class exchange program with a school in Spain -- a program which had been in place for six years.

There were no classes Wednesday at Joseph Koenig High School in Haltern, reports CBS News Holly Williams, but students were encourage to show up anyway, just for grief counseling.

Sixteen of the dead were students, along with two of their teachers. The search resumed in the French Alps on Wednesday for the victims, and clues as to what brought the plane down.

Spelled out in German, a makeshift memorial at the school simply asks the question "WHY?"

Church bells tolled on Tuesday, just hours after the crash, for Haltern's lost sons and daughters. In a town of just 35,000 people, nearly everyone knew somebody who isn't coming home.

In Dusseldorf, where the plane should have landed, and in Barcelona where it took off, families gathered at the airports after hearing the worst news possible from French officials; no hope that anyone on board could have survived.

"Our thoughts and prayers are with those who lost their lives," said German Chancellor Angela Merkel, who was to visit the crash site later Wednesday with her French and Spanish counterparts.

In Haltern, though, the grief was more personal.

"I can't believe it," said the mayor of the town, Bodo Klimpel. "It's a very shocking situation."

Klimpel told Williams two of the girls who died were family friends. Like everyone else in the town, he was still stunned and deeply shaken on Wednesday.

"We've got enough people to care for them, the pupils, and speak with them, and with the parents also if they want," he said.

But like everyone else in his town, he knew it would take a lot more than that, and a lot more time for the healing to even begin.