Other artists have been faced with similar problems, and from
what I've read, one way around this is to have the charity purchase
the items from you at market value, and then donate the money right
back to them.
careful, the IRS can “telescope” certain transactions if they feel
that the end result is a tax evasion. You might get away with it,
but under audit it might not stand up.
Volunteered time is also non-deductible, just like time spent on
making an object. So, as an accountant, if I do the books for a
charity, I cannot deduct my time donated even though I am a trained
and active accountant.