Answer:
There are many perspectives for seeing this question. Some might say yes and some might say no.
But it depends on what they watch and how long do they watch. For example if a kid watches something he shouldn't and from something he is learning wrong things it makes watching TV wrong if they learn good things then it's good. The question how is important one, as it can even cause problem in child's brain and also their eyes. If the child watches TV for more than 4 hours then it's certainly not good.
Hence the answer of this question will be different from each people but the answers are usually yes, no, maybe yes, maybe no, probably yes, probably no, don't know (usually people don't use don't know if they are asked such question during exams or usually people just don't use don't know so in place of don't know they even use maybe both ).
I hope it helped you.