(CNN)Breaking up is hard to do but Ben Affleck and Jennifer Garner make it look easy.
Affleck, who separated a little over one year ago from his wife Jennifer Garner, told "Entertainment Tonight" that when it comes to co-parenting their three children, it's simple.
"We do our best," he said at the Los Angeles premiere of his new film "The Accountant."
But the 44-year-old did admit that there dad duty he finds difficult -- homework.
"My areas of expertise with the kids are spotty at best," he said. "Not homework. I only play an accountant in the movie. In real life, I'm badly wanting."