Here's a lesson for budding entrepreneurs: don't believe everything they tell you in high school.

When Michael Dubin, the founder of Dollar Shave Club, was at his local public high school, he didn't always get encouraging reports.

His mother Nancy Dubin revealed to CNBC's show The Brave Ones that teachers were unimpressed with his attempts to entertain fellow pupils.

"He started out at the local public high school. And it wasn't the first time that reports were sent home that he was the class clown. That he's never gonna amount to anything was one of the… the conferences we went to," she said.

"If things interested him, he was a fabulous student. If it was a subject that … didn't interest him at all, he was probably a terrible student," she added.

"I don't think anybody would have called me a great student, per se," Michael Dubin told "The Brave Ones."

After working in digital marketing and brand development, and taking night classes in improvisation, Dubin founded subscription business Dollar Shave Club from his apartment in 2012, selling razors online for $1 each. He then sold it to consumer goods giant Unilever for $1 billion in 2016.

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