Due to taxation of their stipends, graduate students often lose out on hundreds of dollars per year. Until the Tax Reform Act of 1986 these stipends were tax-exempt. Please see this petition below, calling on the Obama Administration to return stipends to their tax-exempt status. The petition requires you to create a whitehouse.gov account in order to sign.
https://wwws.whitehouse.gov/petitions/!/petition/reinstate-tax-exempt-status-graduate-student-stipends/rXJf6HlP