Are there any publications which list words of English that one might reasonably expect a child to know? I assume that "father" would be on the list, and "allophone; metallurgy" would not be. As for age of this ideal child, between 6 and 12 is in the relevant range. My need for such a list relates to the question of how English phonology is acquired, especially whether the phonological generalizations that describe a plausible child lexicon are radically different from those describing the entire set of English words (the answer is "Clearly", this is about demonstrating that). My preference would be for a list that is based in actual observation, but a policy list ("children in grade 5 should know these words...") might work.
I found the following link regarding the CHILDES database that might be helpful to you in extracting the list of words you want. The description reads "ChildFreq is a tool that lets you extract word frequencies from the Childes database," and it is located here: http://childfreq.sumsar.net/