MADISON, Wis. -

It is a study in contrasts. During the week Marissa Rosen stands in front of a class at Madison College talking discussing chemistry. On the weekends Rosen walks through the door of the Alliant Energy Center and becomes Dutch Oven, a roller derby star.

"It is just so different," Dutch Oven said.

For the last 9 years she's skated for the Reservoir Dolls, a team in the Mad City Rollin' Dolls league. The Reservoir Dolls are the 2013 champions of the league.

"When you play together and you have this amazing teamwork, you get this rush and this high and it is so fun," Dutch Oven said.

There are also collisions.

"Yeah, we fall down a lot," Dutch Oven said. "We have a saying at Mad Rollin' Dolls, we don't fall, we bounce because we want to get up really quick."

In the classroom, the only collisions that occur involve discussions about particles.

"You could imagine girls colliding on the roller derby track like gas particles colliding except there are not elastic collisions in roller derby because eventually we stop," Dutch Oven said.

The other stark contrast can be seen in the seats of a chemistry classroom and a roller derby crowd. At 8:30 in the morning students sit in the classroom quietly taking notes in preparation for a final. At 7:30 on a Saturday night roller derby fans scream, shout and hold up signs supporting their favorite skaters.

But the biggest difference between the classroom and the roller derby track is simple.

"I'm not allowed to hit people at work," Rosen said.