Recently, one lucky student in her classroom got a big surprise from the Los Angeles Rams.
Crippen calls her lessons "NFeLementary." At the beginning of the year, each student picks a team, does a little research and sends teams a letter. The teams even write back.
"It's just been wild to watch the response from across the league," Crippen said.
This year, her student Nathan chose the Rams. He likes the team's blue and gold colors and helmet.
"I got to teach him all about (Rams quarterback) Matthew Stafford," Crippen said. "So I always take the time - if a team responds back via letter or just does something in general - I always want to not just give a gift, but I also want to give the gift of learning and teach them about the team."
The student's letter got a response from the Rams' social media team.
Video on Crippen's Instagram page shows Nathan reading the Rams' letter and opening up a box filled with gifts, including a Sean McVay bobblehead, a Rams foam finger and Rams backpack.
Kurt Gies, the Rams' director of social media and influencers, described Nathan's letter as "absolutely the cutest thing."
"We just can't speak highly enough of the work that Mary's doing and how she she's associating the story lines and things that happen in the NFL and real life lessons that come with that," Gies said.