The loan forgiveness programs for teachers and public service (after 5 or 10 years) are NOT taxable. Loans forgiven after 20+ years of payment, or dismissed for permanent disability or dismissed for other reasons can be taxable.
My sister had her teacher loans dismissed after 5 years. It was part of a program she entered for professionals and that was the intention all along. She went to school, worked 5 years in this program, and her loans were forgiven, as planned.
Teachers have different programs for loan forgiveness than other public service programs (the ones currently under review by the dept of education). BUT the OP should investigate the programs and know exactly what they require.