You don't deduct the summer camp cost from the UTMA income that is reported on the tax return. Summer day camp is a child care expense, provided that the child was under 13 years old and you meet other requirements. (There is no deduction or credit for overnight camp.) Report the full amount of income from the UTMA account, and claim the child care credit separately.
The income from the UTMA is the child's income. It's not clear whether you are reporting the child's income on your own tax return or on a separate tax return for the child. If you are filing a separate tax return for the child, the credit for child care expenses goes on your tax return, not the child's tax return.
Did you pay for summer camp from your own funds, or did you take money out of the UTMA account to pay for camp? The money in the UTMA account belongs to the child. If you took the money out of the UTMA, then you did not pay for the camp. The child paid for it, so you cannot claim the child care credit. If you paid for the camp yourself you can claim the credit on your tax return.
To enter child care expenses, in the Search box type "child care" (without the quotes), then click the link that says "Jump to child care."
