CHICAGO (CBS) — Thousands of Chicago Public Schools high school students are back in the classroom for the first time since the pandemic began, a day after the Chicago Teachers Union ratified a reopening agreement with the district.

“We fought very hard for this moment, because we felt like it was very important,” Mayor Lori Lightfoot said as she visited Whitney Young Magnet High School on Monday afternoon with CPS Chief Executive Officer Janice Jackson.

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The mayor said it was encouraging to see CPS high schoolers back in classrooms for the first time in 13 months.

“Certainly I think there’s a buzz and energy in the building. Some of these young people are back for the very first time. Others who are more seasoned folks, are coming back and reconnecting with their friends, and then others are remaining remote,” she said.

CBS 2’s Mugo Odigwe spoke with students and parents about the long-awaited return to in-person learning.

It’s the first day in more than a year that CPS high school students are coming back to school buildings, and they are feeling all the things you’d expect; nervousness and excitement.

Just ask Dr. Joyce Kenner, principal at Whitney Young High School, who welcomed students back Monday morning with an elated shout of “We’re back! We’re back! We’re back, we’re back, we’re back! Woo!”

“I’m a little nervous,” said sophomore and baseball player Christian Alvarez.

He’s happy to be back, because – in his words – virtual learning was getting boring.

There are other perks to being back too.

“It makes things a little bit easier on my part, traveling around. I play baseball, and it’s definitely beneficial to just be here,” he said.

Some parents feel the same way about virtual learning.

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Marisol Garcia is glad her son, a freshman, will finally have a close-to-normal high school experience.

“He wasn’t doing too well with virtual learning. So I’m excited for him to be back in the classroom,” Garcia said.

After weeks of negotiations with CPS, the Chicago Teachers Union ratified a re-opening agreement with the district on Sunday.

Both sides agreed on final safety measures for high schools, including a COVID-19 vaccination program for CPS students and families.

The program comes just in time, because Monday is also the first day anyone 16 and older in the city of Chicago can sign up for a vaccine appointment.

“Now that I’m back in school, I have considered it a little bit more, and I am trying to get an appointment,” Alvarez said.

But right now, students and parents alike are simply looking forward to a first day back inside school buildings.

“I’m excited for him. He really needs this,” Garcia said of her son.

“I got a baseball game after school. That’s probably what I’m looking forward to most; and, if not, just getting to see a couple of my friends during lunch, or whatever,” Alvarez said.

Just like with pre-k and elementary students, anyone going back to their schools today must fill out a daily health screening form.

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School staff also will check student temperatures at the doors.