No, you are not allowed to claim your tuition for grad school because your parents claimed you as a dependent.  It is true that the IRS will NOT allow you to claim education expenses because your parents claim you on their return. 

Per the IRS:

If a student is claimed as a dependent  on another person's tax return, all qualified education  expenses of the student are treated as having been paid by that person. ... If a student is not claimed as a  dependent  on another person's tax return, only the student  can claim  a credit.

For more info please visit the IRS website at : https://www.irs.gov/instructions/i8863/ch01.html