I like this wholistic approach. Thinking of the wiki like a human body -- its not a good idea to try to load up on anti-biotics, or to live in an underground shelter. A good soft skin (so they wanna actually touch it) and an ability to fight off most diseases is enough for most organisms.
-S-
Fantasy: You could also show them how Wikipedia has a "self-healing" process, where vandalism is watched and reverted. They can try to vandalise, and they will see, that after some time the page is back as it was (and they will give up ;-) And maybe, by letting them try, they will come back to wikipedia because they like the idea. If you stop them from editing from the beginning, they will surely not get the Idea of Wikipedia.
Give us the link to your pages, so many eyes will watch vandalism and revert it ;-)
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