Many colleges offer employees free tuition for themselves, their spouses, or their children. That makes jobs on campus attractive for parents.
It also benefits many graduate students who teach or do research for the university, especially those in science, technology, engineering or math, said Steven Bloom, the director of government relations at the American Council on Education.
About 27,000 undergrads and 145,000 graduate students receive this kind of tuition waiver, according to a 2012 survey, the most recent data available.
The waiver is not taxed right now, but the House bill would treat it as taxable income.