"It’s changed me. It’s changed my life," first grade teacher Abigail Zwerner told the "Today" show.
Richneck Elementary School in Newport News reopened Monday with stepped-up security and a new administrator.
The school's district superintendent was ousted from his post after the revelations about the warnings came to light.
“We will regret our absence on this day for the rest of our lives,” the parents said in a statement.