"I just finished high school," he told The Sunday Telegraph of Australia. "I passed my test -- I'm free! It was hard doing school and work every day."
Bieber, 18, said his finishing school with tutors while he was on the road was important to his mother.
"That was something my mom really wanted me to do, so I had to do it for her," he said. "I mean, this kind of lifestyle has given me a different perspective on life. I've been able to travel the world. At school, usually you have to do a lot of writing and reading. I'm really not into that stuff. I like to be out there."