Rosen, a point guard, played collegiately at the University of Pennsylvania, where he was an All-American and Ivy League player of the year.

Rosen is Jewish,[1] from the Colonia section of Woodbridge Township, New Jersey, and played for the Penn Quakers men's basketball team from 2008 to 2012.

[3] As a senior, Rosen led Penn back to the postseason for the first time in his career, as the Quakers finished the season 20–13 and made it to the second round of the 2012 College Basketball Invitational.

In addition to leading Penn in scoring, assists, three-pointers and free throws made (105), Rosen was second on the team with 46 steals.

On May 12, 2012, The University of Pennsylvania gave out its Senior Class Leadership Awards at College Hall as part of the weekend's Commencement ceremonies.