GI Bill educational benefits are not taxable as long as they are used for qualified educational expenses.
Amounts your husband received from student loans are not taxable income as long as your husband is required to pay them back.
Educational expenses paid with the money from the loans are treated as paid by the taxpayer for the purposes of claiming an educational credits. Thus if the money from the student loan were used to pay for tuition or books - these are eligible educational expenses and may be used to claim an educational credit.
However - the money which were used for room and board or other living expenses may not be used to claim a credit.
You may find specific requirements for each credit in IRS publication 970 - http://www.irs.gov/pub/irs-pdf/p970.pdf
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