Giving kids accessed to a curated experience online sounds much more feasible than keeping them offline all together, but most parents don't really have the technical know-how to do this themselves (and tech giants like Google, FB, etc. are not interested in providing these capabilities).
But if you download your own separate offline version, it can be whataver you want it to be, and that will be all your users get - whether your goal is to ensure access to the ‘right’ parts, or to disappear the ‘wrong’ parts. You could even start out with the former objective, but end up with the latter situation, depending on how things go.
That isn’t quite the same situation with the definitive version of Wikipedia live on the World Wide Web.
I.e., interpretation...
katabasis: (Suggests sensible guardrails for children)
fritzo: THOUGHT-POLICE!!