"Aside from a $50 per term co-pay, none of those students has to pay a dime in tuition this year, unless they choose to take more than 12 credits a term."

This is simply untrue.  At Portland Community College, tuition this year is $97 per credit.  For a student taking 12 credits, that is $1164 in tuition and maximum Oregon Promise grant is only $1132 per term.  Subtract the $50 copay and tack on at least another $100 in mandatory fees by the college, the student is coming up approximately $182 short per term, not including books.

For a student taking 8 credits, the grant is cut in half.  Tuition would be $776 and the grant only $566.  Again, subtract the $50 copay and tack on at least another $74 in mandatory fees by the college, the student is coming up approximately $334 short per term, not including books.

http://www.pcc.edu/enroll/paying-for-college/tuition/