Youtubik consists of two parts:
On your child's ipad you install Youtubik application. All Youtube videos are now accssible throurg Youtubik.
Uninstall usual "YouTube" application from the iPad so that the child does not watch the video bypassing Youtubik and you can always control him.
Youtubik hasthe same huge amount of videos as the usual YouTube - except for those harmful, which you forbid for the child!
You, parent, go to youtubik.app and control how your child watches videos.
This happens unnoticed by the child. You can access the site at any time from a computer, ipad or phone - and see what the child is watching at and control his views.