Most teachers should qualify for the Public Service Loan Forgiveness (PSLF) program, meaning any federal loans (not private) should be forgiven after 120 payments without incurring the tax burden. As far as I understand, the 120 payments could well be "payments" of $0 if the annual income is low and the borrower is on an income-based repayment plan.

By the way, if you file taxes separately, they typically only take the borrowers income (unless you are on the REPAYE repayment plan, instead of the IBR repayment plan).