More than a million students headed back to school on Wednesday in New York City, marking the first first day of classes during Chancellor Richard Carranza’s tenure.

His day started well before sunrise, with a 5 a.m. visit to a Queens bus depot where the new schools chief snapped a selfie with drivers. He hopped on a yellow bus with two first graders to P.S. 377 in Ozone Park, Queens, to kick off a bustling five-borough first-day tour, a tradition among New York City chancellors to highlight the diversity of the city and their policy priorities.

Over nine hours, Carranza plans to visit a prekindergarten class in Queens, sit in on an Advanced Placement class in the Bronx, eat lunch in Harlem, stop by a charter high school in the far reaches of Brooklyn, and dismiss students on Staten Island. Mayor Bill de Blasio will join him this morning at a class for 3-year-olds that’s part of his administration’s early childhood push.

Our Christina Veiga is along for the ride and will file dispatches all day. Share your first-day-of-school pictures and observations and we’ll include them!

A QUICK BUS RIDE The chancellor usually travels by SUV but took a yellow bus to his first school on Wednesday, a 15-minute ride with first graders Miabella Salas, 6, of Ozone Park, and Salvatore McGrane, 5, of Howard Beach.

According to a pool report of the trip, Salas told Carranza her first priority for the day was to reconnect with friend she missed over summer break.  “I want to play with my friends,” she said. “And be nice to them.”

Carranza was on board with that approach, as well as Salas’s goal of working on her math skills. “Her advice is to be nice to kids today, she agrees that she should have lunch, she’s going to help her friends and she has a backpack full of school supplies,” Carranza observed. “She’s prepared and ready to go.”

The chancellor then sat next to Salvatore. It took a bit for the two to warm up to each other, as Sal was distracted by train tracks and other scenery out the window. “Sal is so over me,” Carranza joked. But they picked up steam as Sal outlined his career plans—becoming a train conductor—and spoke about how much he loved the school bus.

After dropping off his passengers, bus driver Luis Torrero looked relieved and said he appreciated Carranza’s choice to ride a bus on the first day of school.

“That was pretty cool,” he said, according to the pool report. “This is my career, this is my life, being a bus driver. So it’s definitely a good way to start the year.”

PHOTO: Christina Veiga/Chalkbeat
Mayor Bill de Blasio and Chancellor Richard Carranza walk a 3-year-old to his first day of class in Queens.

FIRST SCHOOL STOP At P.S. 377, Carranza and de Blasio walked hand-in-hand with a preschool student, who was wearing a toy firefighter helmet, into the brick school.

In the courtyard outside, Tiffany Anastasia snapped pictures of her 2-year-old son, Luke Acevedo, who was starting preschool.

After making pre-K free and universal for 4-year-olds, de Blasio has pushed to start his signature education policy even earlier — for 3-year-olds. The mayor plans to offer “3–K” in 12 school districts by 2020 — four more than he originally planned. A full expansion will require a substantial influx of state and federal dollars.

The political fight ahead was far from Anastasia’s mind as she posed Luke with a cartoon backpack and snapped photos. She said she heard on TV news that 3-K was available in her neighborhood and signed Luke up, even though the timing of his birthday meant he’d start at only 2.

“He needs friends,” Anastasia said, adding that “it’s a given” that she’d cry after sending Luke off.

Inside, parents eased their children into what for many will be their first classroom experiences. One scene that Christina captured:

AROUND THE CITY Carranza wasn’t the only one taking selfies and grinning for the iPhone camera Wednesday. Parents, students, and teachers around the five boroughs marked the first day of classes on social media.

SECOND SCHOOL AND PRESSER In a wide-ranging press conference, elected officials and educators sung the praises of expanding early childhood education, the mayor projected optimism for scoring admissions changes at specialized high schools, and Carranza laid out some broad goals for the year.

The city’s 3-K program is available in six districts across Brooklyn, the Bronx, and for the first time this year, Queens. About 5,000 students are enrolled in more than 180 schools. The mayor estimated the program saves families about $10,000 a year.

“This was a basic matter of equity and fairness,” de Blasio said. “When kids are 3 years old and 4 years old, they can learn in a way they literally can’t learn later in life. This is this irreplaceable moment.”

Carranza called the first day of school “a momentous occasion.”

“This is our Super Bowl. This is our World Series. This is our U.S. Open, all rolled into one,” he said.

Carranza said he wants to focus on “learning and instruction” this year, calling it the “cornerstone” of the system. He also pledged to “empower and partner” with school communities; foster a learning culture in schools; and shift away from tough accountability to focus on building “capacity” among educators.

Asked about the specialized high schools debate, de Blasio said “I like our chances” when it comes to getting the legislature to approve admissions changes.

DEBATE CLASS AT A THIRD SCHOOL In the Bronx, Carranza stopped by AP classes in two schools that share the same campus to highlight the city’s efforts to bring advanced, college-level courses to more students.

In a U.S. history class at the Cinema School, the chancellor listened as students debated whether schools should arm teachers.

Just a few flights up the stairs, students in an AP psychology class had written what they wanted to learn in the next year on sticky notes. As they debated the question “What is psychology,” the chancellor jumped in to moderate another conversation about guns in schools.

“That’s only going to incite more shootings and more conflicts,” one student said.

Carranza offered his own thoughts, saying he was proud of students who walked out of class last year to protest gun violence. He asked how first responders would distinguish a school shooter from an armed teacher.

“Would that be dangerous?” he asked. “Super dangerous.”

LUNCH BREAK Next stop: P.S./M.S. 180 in Harlem, where Carranza tied a green apron around his waist and served lunch to students. The city has made lunch free for all students after years of lobbying by advocates.

Carranza grabbed a tray for himself and sat with middle schoolers, chowing down on grilled cheese, chick peas, green beans, and an apple as they chatted.

Asked what the education department could do better, the students petitioned Carranza for work and internship opportunities, and more activities that align with their interests. Then it was time for the students to pose questions. One asked Carranza about his goals.

The chancellor answered: “I want one day for people to talk about New York City public schools and never, ever mention that they’re segregated.”

LAST STOPS After lunchtime, Carranza headed to Brooklyn for a quick visit. The chancellor can’t help but linger at each stop, snapping selfies and shaking hands. That left him with little time to spend at Origins High School in Sheepshead Bay, where the “mariachi chancellor” strummed a guitar and sung in Spanish. He told the students to keep practicing and then headed to New Visions Charter High School for Advanced Mathematics and Science III, located on the same campus. Carranza visited an AP computer science class to showcase the Computer Science for All program. On the way out, Carranza shouted his thanks to the school safety agents manning a front desk.

The last stop of the day brought Carranza to Staten Island, where he high-fived first graders as classes let out. School staffers stopped him to take selfies. Carranza happily posed for photos, declared himself just as energized as when he started the day before dawn, and slipped out a side door into a waiting car.