His goal for students is to "take responsibility for your own learning," he said.
He doesn't want to throw his weight around too much and promised to "not get worked up about little things."
"If I can be invisible in terms of the day-to-day operations, fantastic," he said.
Holmgren was already involved at Calvert before his official start date of July 1. He attended an open house April 1 and spoke to parents in the school's new middle school assembly hall.
In June, he held a three-day retreat for administrators in St. Michael's on the Eastern Shore.
"It was an opportunity for them to educate me," he said.
Even so, he has no major changes planned in the immediate future, and said, "My priority right now is to get to know the school."
Continuing a longtime Calvert School tradition, Holmgren and other administrators will shake each student's hand as they walk into school each day.
Holmgren comes to Calvert at a time when the school is winding down an expansion program in recent years and expects to open a new lower school early education wing in time for the start of school Aug. 28.
Calvert is also in good financial shape, buttressed by a $3 million grant in 2003 from the Carey Foundation — whose namesakes, brothers Frank and the late William Carey, both graduates of Calvert.
The school in the midst of a $20 million capital campaign, its first in a decade and third in its history, called "Building on Strength," to increase its endowment, student financial aid and professional development for teachers, and pay for recent construction projects. The campaign has raised $14.7 million so far, spokeswoman Stephanie Coldren said.
"I'm a very lucky person," Holmgren said. "I'm coming into a school that's on very solid footing and is turning out good kids," most of whom go on to other independent high schools in the area, including Gilman, McDonogh, Bryn Mawr, Friends, Park School, Roland Park Country, and the Baltimore School for the Arts, according to Calvert School placement statistics.
The former football lineman hit the ground running July 16, even after staying in the Colonnade Hotel on University Parkway the night before with his wife, Peggy, their sons, Aidan, 12, Owen, 10, and William, 6, and their dog, Max, a 2-year-old labradoodle.
"We met the movers today," he said, adding that he spent the morning at home and then came into work.
He is looking forward to being a Baltimorean, including following the Orioles, although his heart is with his home teams, including the Boston Red Sox, the New England Patriots, the Boston Celtics and the Boston Bruins.
"I like the Orioles," he said. "I'm very happy to see them do well. I'll root for them to be a wild card team in the playoffs."