Future freshman at Columbia University may be required to annotate texts online, but in Daniel Gerling’s First Year Composition class, it’s already happening.

While he teaches popular novels, F. Scott Fitzgerald’s The Great Gatsby and Horatio Alger’s Ragged Dick, Gerling’s teaching style isn’t so by-the-book. He requires students to write five annotations online using Rap Genius, a “hip-hop Wikipedia” started to help people understand and interpret rap lyrics.

“Typically in an English class, you write a paper, the professor grades it, you get it back and then it sort of disappears,” Gerling said. “But here their work is up on the web—it’s being commented on by users from all over the world. There’s a kind of permanence to the work.

Since Rap Genius started, novels, legal case speeches and historical documents have been added to it. Several teachers nationwide use the site in a similar way, to teach biology or French, according to Jeremy Dean, Education Czar with Rap Genius, which also has Poetry Genius and News Genius counterparts.

Students still discuss The Great Gatsby and Ragged Dick in class, but online annotations add to their education outside of the classroom, Gerling said.

“It brings the text to life in a way that a standard book wouldn’t for all students,” Gerling said. “Students are digging into the words or passages themselves and doing active research, ultimately contributing to what’s going to be, in a couple years, a fully annotated text.”

For freshman Ryder Reed, the Rap Genius look and user-friendly platform stands out. The site’s users, or “scholars,” can add text, pictures, video, maps and hyperlinks to annotations.

“The site has really cool graphics and an easy-to-use interface,” Reed said.

Freshman math and computer science major Laura Tinker said Rap Genius’ interactive nature helped her learn the way she learns best—with pictures.

“I’m more of a visual learner,” Tinker said. “So Rap Genius helped me figure out the complicated plots and the symbolism of the texts.”

In an interview with TechCrunch, co-founder Mahbod Moghadam called Rap Genius “a tuition-free university.”

Gerling, who includes Rap Genius in his syllabus and counts online annotations as   10 percent of the student grade, says there’s a chance that readers might lose the individual experience of digging in a book for themselves.

“That’s a potential danger of Rap Genius, for sure,” Gerling said.

Gerling said Rap Genius changes the way he teaches, for the better.

“I think it’s necessary to bridge the generation gap, to work with them on mediums that they feel comfortable with and have experience with,” Gerling said.