The superintendent gave the graduating seniors a special salute. The Class of 2011 at High Point High School in Prince George’s County had witnessed many troubles, from a high truancy rate to the mid-year departure of its principal after video of a half-dozen teenagers pummeling a student surfaced on YouTube. “It hasn’t been an easy year,’’ Superintendent William R. Hite Jr. said to the sea of blue and yellow robes last week at the Comcast Center. “But it’s because of your leadership, your work ethic and your commitment that we’re sending you out to the world prepared.”

As the school year ends, educators, students and community activists say High Point High is making a comeback. Officials say truancy is down. Talk in the hallways is more about a culinary arts program than the food fights that had afflicted the campus. Since March, there hasn’t been a single major fight.

Hite credited the acting principal, Rebecca Garcia, whose name elicited cheers at Monday’s graduation.

One recent day at the 2,300-student school in Beltsville, Garcia walked out of her office, carrying a jangling set of keys.

“Are you in position?” she said into a walkie-talkie, instructing other administrators to take their posts in the hallways. As the bell rang, the linoleum floors were flooded with students dressed in the school uniform of blue polo shirts and khakis.

“Let’s go!” she yelled. She smiled at students pumping their fists to power through the crowd. She frowned at one wearing earbuds.

“Tu sabes las reglas,’’ Garcia said in Spanish — “You know the rules.”

“Sorry,’’ the student responded, taking them out and putting them in a pocket.

In six minutes, the hall was again calm. Garcia exhaled.

Over the past few months, so has the community.

“An absolute breath of fresh air,” said Karen Coakley, a lifelong Beltsville resident and a member of High Point’s Class of 1975 who now heads a local neighborhood association. “This was absolutely the worst year I’ve ever seen at High Point. Inside a week of her being there, we saw an immediate, instantaneous change. Night and day.’’

Located on Powder Mill Road in northern Prince George’s, High Point is one of the county’s oldest schools and among its most diverse. It made “adequate yearly progress” last year, but its graduation rate is barely 80 percent.

Many students come from immigrant families with roots in Central America or Africa; 34 languages are spoken in their homes.

Three years ago, parents overwhelmingly voted to require school uniforms as a way to help prevent gang recruitment. Some also worried about chronic attendance problems.

“Students would come off the bus to go to school, then go into the community instead,’’ said Marcus Smallwood, past president of the parents’ association. “And parents were not being notified that their child wasn’t in school that day.”

Various officials shared those concerns.

Del. Joseline A. Pena-Melnyk (D-Prince George’s) said she sometimes pulled into the parking lot and observed rampant truancy. County school board member Edward Burroughs III (District 8) showed up at the school one day in January to speak with then-principal Michael Brooks about the issue. (That month, the school board voted to reprimand Burroughs for failing to obtain the superintendent’s permission to make the visit. The Maryland State Board of Education in April upheld the county board’s action.)

Over the school year, some students reported an unsettling escalation in campus violence. Brooks, according to parents, said the reports were “overstated.”

Hite was quietly monitoring the situation, but he said he worried about the timing of a switch in school leadership, because “changing a position in the middle of year can be disruptive.’’

Then came the YouTube video. In early March, someone with a smartphone recorded the scene of a group of students kicking a classmate in the head. The footage was briefly posted on the Web. Days later, Hite named Garcia acting principal.

Garcia had worked at High Point for a decade, as an English language teacher and then as an assistant principal. She was known for her easy rapport with students.

“If you treat the students with respect, if they know you and what the expectations are, then they will rise up to the challenge,’’ Garcia said. “I’m very happy with the way the school is operating now. Everyone wants to improve this community.’’

Working with the county sheriff’s office, the school generated a new safety plan. Students were allowed only one way into the building in the morning — through the cafeteria, which made it more difficult for would-be truants to leave. At the end of the day, teachers dismissed students by floor for crowd control.

Garcia expanded mentoring programs, including some connected to local universities, to help reach at-risk students. And she held more activities, such as a career fair and an Advanced Placement class fair, to entice students to stay in school.

From her first-floor office window, she watched how many students the truancy officers would return to school. Before she was named acting principal, Garcia said, she could see 50 a day. Nowadays, it’s more like one or two.

“It’s easy to see the benefits of these changes,’’ said Sharon Taylor, a spokeswoman for the sheriff’s office. “In fact, since we’ve made them, we haven’t had any” major fights, she added.

School officials also added a fourth lunch period to the school day to help keep the cafeteria calm. Three years ago, the school had eliminated a fourth lunch period so students could have more class time. But the result was a cafeteria so crowded that some students couldn’t get their lunch. Others would become agitated, leaving the place a mess.

Now there is order at lunchtime. Two administrators keep watch to ensure that not so much as a grape rolls onto the floor.

“There used to be a lot of negative energy around here,’’ said Reema Taylor, a junior. “But now it feels different. I hope it lasts. Now kids are starting to get excited about going to the school.’’