4. Robert Downey Jr.
The Iron Man star dropped out of Santa Monica High School after his junior year when his father gave him an ultimatum to “either show up [to school] every day or quit and get a job.” The move definitely worked out for the A-List actor. Similar to DiCaprio, Robert Downey Jr. dropped out of high school before graduating and made his way into film-making through his father’s films before branching out as he got older into other features, and eventually, after some time in rehab, landing in some major roles like that of Iron Man, that have since solidified him as a major name in Hollywood. He did eventually receive his GED while serving time. “I did not (ever finish high school) — I got my GED in the penitentiary. One block over would be where I got my first DUI — although I didn’t have my license yet,” said Downey Jr. in an interview with Esquire.