I would find the noise level you are describing troublesome and annoying too.
However, there is very little you can do about it.
Parents these days, perhaps it always was the case, become offended if you say anything and will definitely not attempt to control their children.
The attitude is "children are children and have to be allowed to play".
Yes, well neither you nor I am denying that - we are only asking to be able to enjoy our own gardens!
If you decide to speak to the parents, start by offering a compromise, for instance, "Obviously, your children enjoy playing in their garden, but I must admit, I find the noise very tiring.
Could we agree that they don't shout, sing or kick balls about between two and four in the afternoon, please? You see, I have to rest then.
If it is your fence, I think you can ask that the boy does not kick his ball against it at any time. If it is a party fence, or theirs, they can pretty much let him do what he wants.
If the fence is on your ground, I would simply take it down and put up wire netting that shrubs can grow up instead.