The controversy over graduation rates in Prince George's County continues to swell.

Frustrated parents and union members attended a school board meeting in Upper Marlboro Thursday night to address allegations involving the public school system.

Over the last few weeks, some parents have claimed the graduation rate presented school system administration is an representation of how many students are actually prepared to enter into higher learning.

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"This administration is quick to deny rather than investigate allegations that are brought forth," said parent Donna Young.

Dr. Kevin Maxwell, CEO of Prince George's County Public Schools, defended the school system during the board meeting.

"There has been no systemic effort ordered by me or others acting on my behalf to promote students in order to inflate graduation rates," he said.

However, that defense did not calm the concerns of all parents.

"I have been worried about the administration," said parent India Byrd. "I would like to see changes."

Many people also left the board meeting frustrated that only 15 people were allowed to speak during public comment. Some people told WUSA9 they felt the move was made to intentionally cut out criticism from the night's discussion.