FOXBOROUGH, Mass. -- Two weeks ago, New England Patriots tight end Rob Gronkowski was a surprise guest at a Massachusetts middle school. This Saturday, he'll welcome a child to Gillette Stadium as part of the Make-A-Wish Foundation.

Everyone knows about the force that Gronkowski is on the football field, but this is the side of him that isn't often talked about.

Few Patriots give as much time to charitable and community endeavors as Gronkowski.

"I don't think that Rob has ever had a bad day," owner Robert Kraft said. "His happy, go-lucky attitude is infectious, which makes him a great ambassador when he is out in the community."

Such was the case in Gronkowski's most recent community appearance, on Oct. 20 at Holten Richmond Middle School in Danvers, Massachusetts. The parents of two students had bid on an auction item at the annual Patriots Charitable Foundation gala to bring Gronkowski to school, which is the second year the star power of Gronkowski has raised big money for the franchise's charitable arm.

The visit was a surprise to many, and as is usually the case wherever Gronkowski shows up in New England, a frenzied excitement erupted when he arrived -- from students and many staff members.

"It's all smiles, the whole school going crazy, everyone going wild," Gronkowski said. "When it's like that, it is fun for both parties."

Gronkowski answered questions at a school-wide assembly, took selfies, and then had a meet-and-greet with 30 students as he signed autographs and taught them how to spike a football.

"He was so accessible to the kids, down to earth," said Adam Federico, the school's principal. "He was at their level and they really enjoyed how authentic it was to spend time with somebody like him. The message was great to the kids, about the importance of being involved with sports and activities in school, and I think they took it to heart."

That appearance came five weeks after Gronkowski greeted military members and their families. The Department of Defense event, coming two days after the Patriots' season-opening win over the Pittsburgh Steelers, was for families who are adjusting to having a loved one overseas.

In July, Gronkowski visited Boston Children's Hospital, teaming up with a local foundation that raises funds for cancer research. Gronkowski has shaved his head at the foundation's annual buzz off event each of the last few years.

In June, he was at Massachusetts General Hospital as part of an employee recognition and volunteer program. Prior to that, he was part of the team's "trophy tour" to Foxborough schools in which the Lombardi Trophy was shared with students. He was also part of a Play 60 event in local schools to promote healthy diet and exercise.

Kids raced to decorate their favorite Patriots players like Christmas trees during the Patriots' annual holiday party. Courtesy of the New England Patriots

And he's always a regular at the team's annual children's holiday party where kids decorated him like a tree, as well as volunteering as part of the Patriots' annual Thanksgiving Goodwill event in which turkey baskets are donated and delivered to families' cars.

"If I call him to do something, he'll do it for me," said Donna Spigarolo, the team's director of community relations. "His enthusiasm is contagious, no matter where he goes, and he always brings a smile to the room. It's a joy to work with him."

Spigarolo recalled her first meeting with Gronkowski during his rookie season in 2010, as he was at a Patriots community event in which a new playground was being built. The two sat next to each other on the bus to and from the event, and by the end of it she remembers Gronkowski asking to be part of more of them.

He often was, before his rising profile changed the dynamics a bit.

"As he became more of a star, his time became torn between different places and he couldn't be with me every week," Spigarolo said.

Gronkowski's tough run with injuries late in 2012 and into 2013 also didn't help, but he still has exceeded expectations. The Patriots mandate players to make a certain number of community appearances each year, but Gronkowski has easily spiked the minimum requirements over the years, sometimes bringing his brothers and making it a family event. In addition to being part of Patriots-based charity and community endeavors, he also does some on his own.

"You can't do it all. You get many requests all the time, but I still have to focus on football, still have to live my life a little bit," he said. "But there are definitely times during the week when you want to take time out.

"I was always blessed growing up with opportunities and access to facilities, equipment, and playing with my brothers in the backyard to be the best athlete I could be," he continued. "Everyone always helped me out growing up, and everyone now supports me Sunday. So whenever there's a chance to give back, to the community, to the less fortunate kids so they have the opportunity to gain the most potential they can in their life to be success, it's always good to do."

On the field, Gronkowski's impact arguably has never been greater, most recently evident as he caught 17 passes for 221 yards and two touchdowns in the club's last two victories, and was credited by head coach Bill Belichick for creating opportunities for others even when he didn't register on the stat sheet.

He's also been productive in the marketing game, saying that he lives off his endorsement money and has never spent anything that he's earned as part of his contract. In fact, the first question Washington reporters asked him on a Wednesday conference call was about a party cruise he's sponsoring after the season.

Stories of Gronkowski the party man are plentiful, as are those of Gronkowski dominating on the football field. But even as his star has risen, and demands on his time have grown, he's still stayed grounded to the point that following through on community and charity events is important to him.

And, more importantly, to those he's reaching out to.

"I'm not sure Rob even knows how impactful his visits to schools and hospitals are," Kraft said. "I think he just genuinely enjoys meeting people and making them happy."