@Sarah, That is such a tough question because the answer is really "it depends", which isn't very helpful.
I will tell you that I feed our family of 5 (my kids are almost 2 up to 6 1/2, and eat more than I knew that kids could eat!) in Canada for $450, although we are experimenting with upping it to $475. We eat fully real, whole foods and probably more than 70-80% organic or uncertified but organically/sustainably grown.
I know of several other frugal real foodies with 2 young kids (in the USA, not Canada) who eat in the realm of $300-$450. Some that are more purist in what they buy or with more/older kids might be in the realm of $500-700. I'm sure there are some who spend more, but probably not the ones who are also particularly budget conscious.
The "it depends" is really about where you live, which resources are available to you (farmers, certain markets or stores), how big your appetites are, whether you eat a lot of grains or go heavy on animal products, etc.
I'd love to hear others weigh in on their expenses, but let's all just keep in mind how very relative of a topic this is. No getting down on yourself with comparisons, ok? :)
