Hi Henning,
Just to put you at ease: I am not making such a proposal currently, but I want to discuss options at Wikimania and other community events.
I must however correct you on "Educational content is per se suitable for all ages". This is simply not true. Most educational is written with very specific age groups in mind. A three year old will learn from a specific category of books (most of them clearly marked with an age recommendation), while certain other topics (including sexual education, drugs, violence) are introduced in educational materials targeted at older kids. I know of no educational system in the world that doesn't apply some sort of age appropriate structure.
Dimi