At Tulip Grove Elementary, much of the building was new — tall windows, gleaming classrooms, an indoor garden and a book-stocked media center. And so it seemed only fitting that as the academic year opened Tuesday, the newest leader of the Prince George’s County school system was there in Bowie, Md., to cheer the change.

“We’re excited to see you, and we know your teachers are excited to see you,” Monica Goldson, interim chief executive of the county’s schools, told Tulip Grove’s 325 students as she wished them “an amazing first day.”

The school was one of hundreds across Maryland that welcomed students for the 2018-2019 academic year, as the state projected another year of record enrollment and as high temperatures made for a hot opening day. For a second year, most schools in the state started classes after Labor Day, in keeping with a state order. The steamy weather prompted Prince George’s officials to announce that classes will end two hours early Wednesday.

In the Washington suburbs, with Maryland’s largest school systems, Montgomery County expected more than 163,500 students, and Prince George’s made room for more than 134,000. Both systems continue to report rising enrollment, and both pointed to new initiatives as leaders pledged to improve student learning and success.

In Prince George’s, Goldson crossed the county, from Bowie and Riverdale to Upper Marlboro and Forestville, greeting parents, students and employees while sounding a message of coming together in a school system where many are looking for a reset.

Last school year, Prince George’s was mired in scandals over questionable pay raises and inflated graduation rates. Earlier, it had lost its federal Head Start grant and reeled after a major sex abuse case raised questions about its practices and oversight.

“I feel like it’s a new beginning,” Goldson said, noting that elected officials and school board members joined her as she toured schools. “We want to show a united front and that it really is about children. We have to get beyond some of the issues we have had to face.”

Goldson, a 27-year county educator, was named to the top job in July, following the departure of Kevin Maxwell from the chief executive job. Maxwell had three years left on his contract as controversies intensified and calls for his ouster grew louder.

Goldson has described herself as a hands-on leader who will make data-driven decisions and engage the community as she seeks to make the school system more responsive. A graduate of public schools in Prince George’s, she also sent her children there.

“Hopefully, what they will feel is a different level of accountability than they felt before and more honesty and transparency,” Goldson said. “Every day won’t be perfect, but when it’s not, we’re going to own it, and we’re going to talk about what we’re going to do to improve and make it better.”

Goldson said she considered public perception of the scandal-plagued school system to be among its greatest problems. “We’re working extremely hard to change the narrative about Prince George’s County,” she said.

She said she has moved to correct improperly given pay raises and has supported efforts made by outside investigators to take another look at graduation rates. A report last year found widespread problems, and the new investigation is examining the district’s efforts to fix grading and graduation-certification practices.

New initiatives in Prince George’s include an app called “Here Comes the Bus” that provides information about bus arrival times and an apprenticeship program to give students experiences with carpentry, plumbing and other fields.

Theresa Mitchell Dudley, president of the county teachers union, joined Goldson and other officials in looking ahead. “We’ve been through a lot of trauma in the system, and this is a good opportunity to start anew,” she said.

Nikki Ham, a mother of two who lives in Upper Marlboro, said she appreciated efforts to be more transparent with parents. After the challenges of the past few years, she said, “I’m optimistic; I’m hopeful.”

In Montgomery County, a new school opened in Rockville — Bayard Rustin Elementary — while several others were expanded and the Thomas Edison High School of Technology was rebuilt. District officials said key areas for the year ahead include early learning, career preparation and access to advanced courses.

At some places in Maryland, the first day of school was interrupted by the heat. In Montgomery, Brookhaven Elementary dismissed early because of air-conditioning problems. Schools in Baltimore City and Baltimore County were forced to close for the day or let out early because of high temperatures and a lack of adequate cooling systems.