A local group overseeing education is illiterate (10)
I believe the answer is:
unschooled
'illiterate' is the definition.
(thesaurus)
'a local group overseeing education' is the wordplay.
'a local group' becomes 'uned' (I can't explain this - if you can you should give a lot more credence to this answer).
'overseeing' means one lot of letters goes inside another (I've seen this in other clues).
'education' becomes 'school' (school is a kind of education).
'uned' going around 'school' is 'UNSCHOOLED'.
'is' is the link.
Can you help me to learn more?
(Another definition for unschooled that I've seen is " Lacking formal education".)