I'd love to compile a list of some of the companies who make minimalist shoes for kids. I know a few:
Soft Star Shoes (babies, toddlers, kids and adults) http://www.softstarshoes.com/ Vibram (sizes 29-34) http://www.vibramfivefingers.com/products/Five-Fingers-Boys-KSO.htm Vivo Barefoot (sizes EU 27-39) http://www.vivobarefoot.com/us/kids.html/ Certain water shoes
I've heard Merrell will have some, but haven't seen them, yet.
What else is out there?
You have to include huarache sandals, although I have not yet tested with my kids (my daughter said "dad, I want to make sandals like yours!").
Of course there are custom kits available, also saw that Unshoes mentioned this:
http://unshoes.wordpress.com/2010/06/09/childrens-sizes/