If you do it for free or GC$: Good Idea!
If youlet it cost sth. like earnwithgoogle.com then: VERY BAD IDEA.
Adsense Trick: Place images above Google Ads and the people will look at them. This can boost you earnings / times. For more details look at my blog and ( if you cannot read & understand german ) translate it with Google!
greetings,
lionstarr
EDIT: UUps, didn't read all of your post!
Sorry. therefore the next tip: there's a webinar for Earning more with Google Adsense from Google under:
http://www.google.com/services/adsense_webinar.html
Hope this will be good ebooks,
and big thanks to you for the idea.
Again greetinsg,
lionstarr