“If you’re not tired after a section, you didn’t bring enough energy,” he says.

Most undergraduates relish the “creative flexibility,” as CS50 head TF Chartier puts it, of teaching.

Others feel a commitment to give back to the academic communities that have defined their experiences at Harvard.

“I didn’t want people to rule out entering this new major at Harvard [Biomedical Engineering] just because of what they’d heard about its fundamental intro course,” says ES53 TF Anugraha M. Raman ’12. “I hoped that by TFng this class I could more directly convince my peers what an exciting and engaging field they were entering into.”

For all the time it took, Danz’s commitment to his role as head TF was one of the “anchoring” factors that convinced him not to accept an offer to leave college to work for a start-up company. Now, he says, he is glad he never left.

Ultimately, most undergraduates who take on the role of peer-instructor love what they are studying and love to share that passion. Their enthusiasm is usually hard for students to miss.

“One of my warmest moments that I’ve had at Harvard was reading the CUE evaluation that students wrote for me,” reminisces Valtis. He shares some of the comments students have written: “‘You taught me math,’ ‘If it wasn’t for you I would have failed the class,’ and ‘You made me like math or calculus.’”

For Valtis and his peers—many of whom are considering careers in academia thanks to their experiences—those comments are only the beginning.

—Staff writer Radhika Jain can be reached at radhikajain@college.harvard.edu.

—Staff writer Julie R. Barzilay can be reached at jbarzilay13@college.harvard.edu.