CLEMSON, S.C. -- Now we know the real reason Clemson All-America defensive tackle Christian Wilkins decided to return to school for his senior season.

He wanted a stiffer challenge. He wanted to teach kindergarten.

Wilkins, chuckling at the thought, isn’t quite ready to go there, but he does have a new outlook on school teachers. That’s because Wilkins has been moonlighting as a substitute teacher the past few weeks and even dared to fill in one day in a pre-kindergarten and kindergarten class at James M. Brown Elementary School in Walhalla, South Carolina.

“It was fun, but took a lot out of me,” said Wilkins, throwing his eyes wide open and exhaling slowly. “I felt like Arnold Schwarzenegger in ‘Kindergarten Cop’ with all those little kids. Talk about energy, but it was a real cool experience.”

Defensive tackle Christian Wilkins has been moonlighting as a substitute teacher the last few weeks. Joshua S. Kelly-USA TODAY Sports

And not just for the kids, who were mesmerized by their new 6-foot-4, 300-pound instructor.

“The other teachers were the ones who knew who I was because so many of them are lifelong Clemson fans,” Wilkins said. “Some of them would kind of poke their heads in and take slow walks past the classroom, just taking their time. But the kindergarteners ... they just see me as a giant. They love being affectionate and having attention.”

Ashley Robertson, the principal at James M. Brown Elementary School, has three degrees from Clemson, and the only Clemson football games she’s missed over the years were the ones when she was in the hospital delivering her three children. So when she got the news last week that Wilkins would be filling in at her school, she in her own words went full-blown “fangirl.”

In fact, when she received the text message that morning while getting in the car to take her kids to school, she let out a yell rivaling anything you might hear at Death Valley on Saturday afternoons in the fall.

“I was screaming at the top of my lungs, and my kids were wondering what was going on,” Robertson recounted. “I was the first person to go meet him and take him to the office. He was great and wanted to keep it very professional, so we made everybody aware that while we did have a national champion among us that we didn’t want to bother him for pictures and autographs. It was clear he was there to do his job and not for publicity.”

When Wilkins first walked into his classroom, the kids were all sitting on the carpet and waiting. And as their towering substitute entered, one of the kids immediately piped up and exclaimed, “That is one big Mister right there.”

Robertson now wishes that she would have taken one picture of Wilkins that day.

“I was walking behind him in the hall, and he was holding a little girl’s hand and escorting her back to class. It was adorable,” Robertson said. “They loved that he took them to PE and played with them, played popcorn bingo with them, but he’d also get down on the carpet with them and help them with their math stations. He was a natural.”

Clemson coach Dabo Swinney isn’t surprised. He said Wilkins will frequently stay after practice and help with the younger defensive linemen while they’re getting extra work on technique and pass-rushing moves.

“That’s typical Christian,” Swinney said. “He’s one of those guys who’s always going to do everything he can to leave it better than he found it.”

Wilkins, who has already earned his undergraduate degree at Clemson in communications, had to go through the proper protocol and be approved before being added to the substitute teacher list. He has also filled in a few days at Walhalla High School in the Oconee County school district in upstate South Carolina.

His pay is a robust $80 per day, which is just a blip of what Wilkins would have earned had he turned pro. But he said the experience is priceless.

“I love working with kids and empowering them,” Wilkins said. “It’s challenging, a lot more than you think, and sometimes more challenging than anything on the field.”

Wilkins joked that one of the first things he did was try to find the teachers' lounge.

“You always thought teachers don’t really do much as a young person, but you see how much goes into it and how tiring the days are,” he said. “You have an imaginary sense of what teachers actually do and always thought a teachers' lounge was a real thing. I had this whole perception that everybody was sitting around in there smoking cigarettes.

“Maybe back in the day, it might have been like that. But not now. It’s work, a lot of hard work, takes a lot of planning, and you better be prepared for just about anything.”

Even the nuances of popcorn bingo.