The 31-year-old rocker was taught by his uncle who would let him get away with more mischief than other students during lessons and would bend the rules for his nephew at the school in Tennessee.
In an interview with UK station BBC Radio 2, he revealed: ''My uncle was my school teacher and would let me cheat, I was valedictorian in my class thanks to him.
''He only did it [let me cheat] because I had two jobs and went to school, I had reasons, Nathan and Jared applied themselves a little more than I did.
''Everyone used to say I looked like him, we had this bond, he got me through some tough times, we were all really good [at school] we were athletes, we were all pretty smart.''
The valedictorian is the title awarded to the student who delivers the closing or farewell statement at a graduation ceremony and the chosen valedictorian is usually the student with the highest ranking among their graduating class.
Kings of Leon drummer Nathan Followill - Caleb's brother - has now gone back into education and dreams of becoming a teacher when the band stop touring and recording in the future.
Nathan, 34, said: ''I went to college, I'm six credits away from getting my degree in education, once the band is finished I want to teach history and coach basketball, it was our sport.''
Her parents weren't too fond of the idea.
The flat at Hauptstrasse 155 was where Bowie and Iggy lived between 1976 and 1978 in the city, which inspired the so-called 'Berlin trilogy' albums.
Grint will star alongside Dougray Scott and Ed Westwick in a 10-part TV series for Sony's streaming platform Crackle.
The Brits teamed up at the Hollywood Rose Bowl to perform a cover of The Purple One's 'Nothing Compares 2 U'.