Khan Academy was a mistake. My kid's school has been forcing them to use it during COVID and it's terrible.

>"Area of Circles" Section
>Teaches him how to find radius, diameter, and circumference
>one of the "quiz" questions ask him to get the area of a circle given the circumference
>he sits there and tries the problem for an hour, can't get it
>finally take a look at the videos and practice questions he went through
>it doesn't even show how to do this with information being given
>video and practice questions just ask "what's the diameter?" when giving a radius of 5, etc. Very simple questions
>have to teach my son everything instead

I don't mind doing this, but I work from home and I can't be with him 24/7 while he does his work. Are there any resources you guys know of for kids when it comes to math? I already printed out worksheets for him. Videos are preferred, so he at least pays attention.