They said, "Thank you for keeping us safe Friday."
It was a first for the 17-year educator, whose assistant principal, June Gordan, had to reassure five students by showing them how the front door locked.
Schools across the state faced a difficult day Monday, welcoming students for the first time since Friday, when 20-year-old Adam Lanza killed his mother at her home, then gunned down 20 students and six adults at Sandy Hook Elementary School in Newtown before killing himself.
All seven Newtown schools were closed on Monday. Six are scheduled to reopen Tuesday. Officials have not announced the date on which Sandy Hook Elementary School students will resume classes at Chalk Hill School in Monroe.
Attendance was a lower than usual Monday in Brookfield, Bethel and New Canaan. Whisconier had twice the typical absences, school officials said.
In Greenwich, the overall absence rate was similar to last Monday's, but at Old Greenwich Elementary School, the number of empty desks jumped from 14 a week ago to 41 on Monday.
Most other schools in northern and southern Fairfield County had normal attendance.
"We did our best to stay calm and confident," Renda said.
He said teachers wanted to show children that they were safe, and that adults would do anything for them.
"We know kids work off us -- our body language and our tone of voice," Renda said. "You have to be able to contain and control your emotions."
Many area school officials spoke of moments of silence Monday for the Newtown victims and their families, and of how students and staff were helped by counselors.
At the same time, students began thinking about reaching out to Sandy Hook Elementary School.
In many Newtown-area schools, educators and students had connections with victims or other students in Sandy Hook.
Brookfield schools created lists of students with ties to the Sandy Hook school. Teachers made sure those Brookfield students were all right on Monday.
"It was hard," said Williams. "The thing we had to do was reassure them all that they are safe."
Fairfield schools put new protocols in place Monday.
"Until further notice, all schools will have a staff member, with an ID badge, stationed at the entrance of each school to greet visitors and direct them to the main office," Superintendent David Title said.
Title said police were stepping up their presence at all schools, and emergency preparedness measures were being reviewed.
"First thing, we had a moment of silence," said Troetti, who wore a green-and-white ribbon in sympathy of the Sandy Hook Elementary School community. "Then we reminded them of the safety protocols, including if they see something suspicious, they should report it."
Monday morning started with small groupings of students talking about how those left behind can honor those who lost their lives, Troetti said.
"We got through the day for sure," Bethel Superintendent Kevin Smith said. "People are putting on a good face for the kids, appropriately."
In Ansonia, counselors were available to talk with any student or staff member, said Tony Gasper, the town's assistant superintendent, and extra counselors were available from the Parent Child Resource Center in Derby.
In Stratford and Bridgeport, police were in and around all schools.
At Beardsley School in Bridgeport, James Morgan, 70, complained that security needed to be tighter because when he reads to a kindergarten class twice a month, few ask him who he is or why he is there.
"We should be asked to show photo ID's," Morgan said. "The woman in the office who gives me a visitor's pass knows my face, but no one else does."
School officials said security procedures were being reviewed.
Danbury Superintendent Sal Pascarella brought in retired staff to add counseling support for teachers and students at the city's 17 schools Monday.
"I don't think there is any formula -- it's listen and provide comfort and safety,'' Pascarella said. "We wanted them to feel comfortable, normal and positive."
Sandra Atanasoff, Danbury's coordinator of pupil personal services, said the district's staff was particularly affected by the tragedy, because Sandy Hook Principal Dawn Hochsprung, who was killed, worked in Danbury for six years, and her husband, George Hochsprung, still does.
In addition, Lauren Rousseau, a teacher killed in the shooting, attended Danbury schools, and her stepmother used to work in the city school district.
"The counselors were very visible in all the schools," Atanasoff said. "They were in the classrooms, fielding questions from kids."
Trumbull Superintendent Ralph Iassogna sent a note telling parents that security procedures were being reviewed.
"Our hearts are filled with deep sadness and overwhelming grief over the tragic events in neighboring Newtown," Iassogna said. "It is truly unconscionable that the sanctity of our schools again has been violated."
Staff writer Maggie Gordon contributed to this story.