"I'm sad because I have to go back to school, but I'm happy that I have to go back to school," fifth-grader Ryan MacIsaac outside TriBeCa's P.S. 234.
"But I know once I walk in those gates, I'll just be happy," added Ryan, 8.
Ryan's peer, third-grader Alex Koster, said even her exciting summer travels didn't diminish the promise of a new school year.
"I really want to see my friends. I really like my teacher," said Alex, 8. "I went to Paris and I went to Switzerland this summer. But school is fun."
Up in Washington Heights, Kimora Bell, 5, was starting her first day of kindergarten at P.S. 28 Wright Brothers, near Amsterdam Avenue and West 155th Street.
"She's happy. She doesn't really know what to expect," said her father, John Bell.
In Corona, students at P.S. 330 began their school year in a new four-story building, near Northern Boulevard and 112th Street. The new P.S. 330 was built to ease overcrowding and is slated to accommodate up to 600 when it reaches capacity in 2017.
Third-grader Christian Espinal was looking forward to seeing the brand new schoolhouse, according to his mother, Maritza Espinal, 28.
But mostly, he was excited "about how I can meet new teachers," the 8-year-old said.
The city kicked off two programs with the first day of school including one that installed cameras around schools in crash prone areas, the Department of Transportation announced.
The day also marked the start of the Department of Education's controversial teacher evaluation system that has angered many educators with what they call its new and untested standards.
But the head of the city's school system defended the new teaching evaluations.
"For the first time in nearly eight decades, teachers will have a more in-depth and consistent way of receiving feedback and support," schools chancellor Dennis Walcott said in a statement commemorating the first day.
"The one thing I've learned from the mayor is try something new. Try something difficult. Never be afraid to fail. Challenge yourself," Walcott said at a visit to Gregorio Luperon High School in Washington Heights with Mayor Michael Bloomberg.
Walcott said preparations for the first day went into the early hours of Monday morning when new books were still being delivered.
"The only piece of advice I can give you, as someone who's about to be unemployed in three months, is: you've gotta work hard," Bloomberg said.
"Your future is in your hands. If you want to make something out of it, you can. And if you don't, you're going to look back one day and say, 'I wish I had,'" the mayor added.
With reporting by Nigel Chiwaya, Jeanmarie Evelly, Colby Hamilton, Katie Honan, and Irene Plagianos.