SALEM, Va. -

50 college presidents in Virginia have written a letter to the Governor and President Obama's Secretary of Education to voice disagreement over a possible college rankings system.

Obama's plan attempts to tie in the amount of financial aid a student gets with the school he or she goes to.

Roanoke College President Mike Maxey signed the letter as the chief representative of private schools in the country.

School presidents are concerned that a one-size-fits-all ranking system isn't possible with over 4,000 colleges of varying sizes and specialties.

"You'd have institutions tempted to drive your performance to the data rather than have the data reflect your performance, sort of a teach to the test phenomenon," said Roanoke College President Mike Maxey.

The ranking system hasn't been implemented yet.  Part of it would attempt to create more transparency about things like median income after graduation.   

Maxey says Virginia is one of the states that already does that.