do you teach your child in their homework or they have a tutorial class?

When I am free, I'd like to be with my kid when he does his homework, It's a happy time to teach my son singly. But when I'm busy, I'm in no mood to do so, so I send him to a tutorial class. Besides, some subject is beyond me and I find I'm not good at teaching him in the lesson, I also ask help from his teacher or tutor.