"I have never considered myself a very smart person, for a lot of reasons," he tells T, The New York Times Style Magazine. And that made his teen years difficult.
"Not having early success on that one path messes with you," he admits. "You get lumped in classes with kids with autism and Down syndrome, and you look around and say, 'Okay, so this is where I'm at.' Or you get put in the typical classes and you say, 'All right, I'm obviously not like these kids either.' So you're kind of nowhere. You're just different."
He believes "the system is broken. If we can streamline a multibillion-dollar company, we should be able to help kids who struggle the way I did."
Now, as a top-earning actor and Hollywood producer (who made millions when Magic Mike became a smash hit), the 34-year-old credits the arts with helping him find his way out of the confusion he felt.
Tatum says his parents were not artistic, but he "was drawn to people who knew about movies, art, even fashion." When he moved to New York as a model, "I just learned everything I could from anybody who knew something I didn't," he says.
The Foxcatcher star believes he has a talent for choosing good mentors. "I can look at a person and say, 'They've got something that I want up there in their head. I'm going to do my best to get in there and absorb it.' My mom said, 'Be a sponge.' And so I've learned more from people than I have from school or from books."
While you'd think he has his hands full juggling his busy movie career with being a father to his 16-month-old daughter, Everly, with wife Jenna Dewan-Tatum, the actor has also found time to take up another artistic pursuit – sculpting.
"I could never carve away marble like the ancients," he says of his preference to work in clay. "With sculpting, nothing is cloudy or mystical. It's just about this object, and if you're trying to depict reality, and you do it well, then the outcome is the truth."