With help from Chris Bell of The Aster Group (http://www.astergroup.com),
we set up an Absence Management plan (yeah, weird huh?) that allows us to enter negative manual dollar transactions any time we make a payment on behalf of a scholarship recipient. Then, once they finish their degree and start "working it off", we add a custom accrual table based on their total outstanding balance divided by the number of pay cycles in their "payoff term" and they "accrue" toward a zero balance.
If the employee terminates before they finish their workoff agreement, they are responsible for paying their outstanding balance.
Designing and setting up the plans and procedures was a bear (Chris Bell is a GENIOUS!) and it takes some careful plan/table setup per scholarship recipient, but nothing our scholarship specialist can't handle with some great setp-by-step documentation.