Dave Franco has gone from medical school to undergrad and now, all the way back to high school.The actor, brother of Oscar-nominee James Franco but now a star in his own right, has been cast in the upcoming big screen reboot of the late 80's/early 90's TV cop series, "21 Jump Street." Starring Channing Tatum and a slimmed down Jonah Hill, the film brings back to life Johnny Depp's breakout role as a cop who infiltrates schools, posing as a student, to breakup drug rings.