Across Newtown's sprawling Sandy Hook neighborhood, home to the school where the December 14 attack took place, children ranging from kindergartners to fourth graders boarded buses for the seven-mile journey to their new school.
Chalk Hill Middle School, an unused school in the neighbouring town of Monroe, was refurbished specifically for the students from Newtown, and now bears a new but familiar name - Sandy Hook Elementary School.
At a home across the street from the school, a banner read: "We're all in this together ... together we are stronger."
Mailboxes in the neighborhood had balloons of green and white, the school's colours, and many houses had handmade posters out front reading: "Welcome Sandy Hook Elementary kids."
Heightened security meant media was kept well away, but from a small plane above the new school, children getting off buses were seen running, hopping and skipping through the doors. A stream of parents' cars dropped students off at the main entrance.
Anca Roberto, 35, put her 5-year-old daughter, a kindergartner, on the bus not far from the old Sandy Hook school, still a bullet-riddled crime scene closed to everyone but police.
Roberto said she had been nervous about the return to school until Wednesday, when she and her daughter attended an open house at the new location. Her daughter was thrilled to find her cubby intact, moved from the old school, and she "screeched" when she saw her friends.
The students "hugged, and they played and they were just kids," Roberto said. "The teachers were just amazing."
At the end of the day, Roberto described her daughter's first day back as a normal routine, and "what they needed."
With safety foremost on the minds of parents and officials in the wake of the second-deadliest school shooting in US history, the school was outfitted with a new security system.
A heavy police presence was on hand, too. Armed police officers patrolled the grounds, all outside doorways and sidewalks were under surveillance, and a police checkpoint restricted access to the school to students, parents and staff.
Asked if she was nervous about her daughter's safety, Roberto said: "I was until yesterday. There's just so much supervision. They're in the safest place."
The new school has been decked out as a "Winter Wonderland," with the help of thousands of children from around the world.
Officials tried to mitigate the absence of teachers and staff killed in the attack, including school principal Dawn Hochsprung, by bringing back some former Sandy Hook staff. The school's interim principal, Donna Page, had worked at the school until 2010.
Sarah Swansiger told CNN she stayed for her daughter Abby's kindergarten session, helping with some activities. There was a feeling "like it was the first day of school" and the children "were really enjoying themselves," she said.
Syeda Suriya Ahmed said her son Mamnun Ahmed, 6, a first grader, initially didn't want to go to school but he did go. "He was scared about the police," Ahmed said as Mamnun ate a snack at their home after the end of the school day.
Gabby Giffords to visit; Governor appoints commission
Meanwhile, former US Representative Gabby Giffords, who survived a mass shooting in her Arizona district two years ago, is planning to visit Newtown, the Connecticut lieutenant governor's office said. She plans to attend a private event at a local home on Friday, although her plans may change.
Connecticut Governor Dannel Malloy said he would form a commission to make recommendations on school safety, mental health, and prevention of gun violence. Malloy, who toured the new Sandy Hook school, wants the panel to report to him by March 15 while the state legislature is still in session.
"We don't yet know the underlying cause behind this tragedy, and we probably never will," Malloy said in a statement. "But that can't be an excuse for inaction."
No new details have emerged to explain why 20-year-old Adam Lanza, armed with a semi-automatic assault rifle, two other firearms and hundreds of rounds of ammunition, targeted the school. State police investigators have said it could be months before they complete their report.
Described by family friends as having Asperger's syndrome, a form of autism, Lanza shot and killed his mother, Nancy Lanza, at their home about five miles from the school, before driving to Sandy Hook and embarking on the massacre, police said. He then took his own life as police arrived at the school, which had an enrollment of 456 before the attack, according to district enrollment figures from November.
The massacre in the rural New England town of 27,000 residents about 70 miles northeast of New York City, stunned the nation and reignited a highly charged debate over gun control.
President Barack Obama, who described on December 14 as the worst day of his presidency, has tasked Vice President Joe Biden with assembling a package of gun-control proposals to submit to Congress over the next several weeks.
The National Rifle Association, the most powerful gun-rights lobby in the United States, has rebuffed calls for more stringent firearm restrictions and, instead, called for armed guards to patrol every public school in the country.