Hi,
Many young children, not just FPOC (because this includes young white children from the laboring classes) were "bound out" which means their parents or guardians or even the courts signed papers of indenture - for them to learn a trade. Children in poorhouses were also bound out as a way to relieve the township of the burden of supporting them.
You can read several interesting articles about this online:
http://eh.net/encyclopedia/article/jacoby.apprenticeship.us
http://en.wikipedia.org/wiki/Indentured_servant
Denise