Jack Black isn't a good teacher.
The 'School of Rock' star - who also fronts rock group Tenacious D - has been trying to teach music to his young sons Sammy, nine, and Thomas, seven, but doesn't think he has the right temperament to pass on his knowledge.
He said: "I've been trying to teach my boys how to play instruments but I've discovered I'm not a very good teacher.
"It takes a certain patience that I don't know if I'm gifted with."
The 46-year-old actor - who is married to musician Tanya Haden - is a devoted father and would rather skip a night out to spend time with his boys.
He told Britain's OK! magazine: "Last night I was going to see a movie and I was thinking, 'I'd just like to go home and put my boys to bed. Why am I going out to a movie?'
"So I did a U-turn in the car, went home and talked to them about their day at school.
"They've just started school so they are a little stressed. Talking to them about their day, that's what really gives me joy."
But the 'Kung Fu Panda 3' star hopes his sons don't follow in his own rebellious footsteps.
He said: "I'm in trouble. I hope they're not going to be like I was, but I know they probably will be. We'll see."