Teach eggheads to go without old money (7)
I believe the answer is:
educate
'teach' is the definition.
(to teach someone is to educate them)
'eggheads to go without old money' is the wordplay.
'eggheads' becomes 'ee' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'to go without' indicates putting letters inside.
'old money' becomes 'ducat' (historical type of coin).
'ee' placed around 'ducat' is 'EDUCATE'.
Can you help me to learn more?
(Other definitions for educate that I've seen before include "what teacher should do, to be effective" , "Teach - instruct" , "Impart learning" , "Team" , "teaching style" .)