At Dayton's Bluff Elementary School in St. Paul, parents dropped off their children as part of their daily routines Monday morning, but not until after discussing the Sandy Hook tragedy.

At Garlough Environmental school in West. St. Paul, students and parents were greeted by a police officer.

Teachers and parents across the country were wrestling with how best to quell children's fears about returning to school for the first time since the killings at the Newtown, Conn., elementary school.

Dennis Carlson, superintendent of Anoka-Hennepin School District in Minnesota, said a mental health consultant would meet with school officials Monday, and there will be three associates -- one to work with the elementary, middle and high schools, respectively. As the day goes on, officials will be on the lookout for any issues that arise, and extra help will go where needed.

"We are concerned for everybody -- our staff and student body and parents," Carlson said. "It's going to be a day where we are all going to be hypervigilant, I know that."

When one mother pulled up and saw the officer at Garlough, her first reaction was "What happened?" She was relieved when she learned the officer was there to meet and greet the students as they walked in.

In West. St. Paul, the district sent a note to parents over the weekend advising them of the best ways to talk about the shootings.

At Dayton's Bluff, Dawn Blasen said she had tried to shield her two kids from details of the shootings during the weekend. But news coverage came up on the radio while she was taking her son, Andrew Williams, a second-grader, to school, and he immediately asked: How could the shooter get guns?

"I said, 'I wish I knew,' " she said.

Blasen said she was angry about the shootings but that her son was set to go about his day.

"I've got to give him props for that. If I were in second grade, I'd say, 'Mom, I'm not going to school,' " she said.

In an effort to ensure their students' safety and calm parents' nerves, school districts across the United States have asked police departments to increase patrols and have sent messages to parents outlining safety plans that they assured them are regularly reviewed and rehearsed.

Some officials refused to discuss plans publicly in detail, but it was clear that vigilance will be high this week at schools everywhere in the aftermath of one of the worst mass shootings in U.S. history: Twenty-six people were killed at Sandy Hook, most children ages 6 and 7. The gunman then shot and killed himself.

Connecticut Education Commissioner Stefan Pryor said his agency was sending a letter to school superintendents across the state Sunday evening, providing a list of written prompts for classroom teachers to help them address the shooting in Newtown with their students.

"Many schools planned to hold a moment of silence Monday and fly flags at half-staff.

Maria Baca, Anthony Lonetree and The Associated Press contributed to this report.

Heron Marquez • 952-746-3281