When Should Children Take Communion?

Evan Curry asks the question when should children take communion on his blog Promise and Peace.

You know you’ve built a personal brand up when the first comment is: "When did this become Everyday Liturgy?"

All jokes and hubris aside, it is an interesting question and one that most don’t really give much thought to other than to defer to the parent.

I think this is symptomatic of the larger problem of membership/confirmation within Protestant and evangelical churches, that no system really exists.  So how do children grow into members and participate?