For one brief shining moment I thought Apple had a good kid platform ....
...As a computer, his iPhone has one large advantage over his desktop accounts. On the desktop Apple and Google together have totally broken OS X Parental Controls (MobileMe is the worst). On the iPhone, once you remove Safari and YouTube, you have Wikipanion and and Wolfram Alpha and Google Earth and Public Radio.app and New York Times.app...That was before my intrepid 13 year old tutored me.
The problem is that a lot of iPhone apps use WebKit, and blocking Safari doesn't block WebKit.
So Google Earth has a Wikipedia layer. Click on the W icons, and it launches WebKit. Click around a while, and eventually you get to places I don't want my kid to go.
Scratch Google Earth.
AppBox Pro has lots of little tools he might like -- but it also includes iGoogle. (Why? Don't ask me.)
Wolfram Alpha looked good. Math, research, but no web. Oops. Except for the "Search the web" link at the bottom of every page that opens an embedded WebKit page.
Scratch Wolfram Alpha.
Houston, we have a problem.
Update 10/4/10: Google's AdMob ads give YouTube access from Pandora.