Heidi Ramirez, the most outspoken member of the Philadelphia School Reform Commission and the first Latina on the board, resigned her position this evening.

Fighting back tears, she read a statement saying she had submitted to Gov. Rendell and the commission her resignation today. She will remain on the panel until a successor is named.

Ramirez, who holds a Ph.D. and is the head of Temple University's Urban Education Collaborative, was earlier this year nominated by Gov. Rendell to serve a five-year term on the commission.

Rendell once pointed to Ramirez as "the most qualified" member of the commission.

Philadelphia School District Superintendent Arlene Ackerman has been publicly frustrated with Ramirez, often the only commission member to question Ackerman and her staff at meetings.

Ramirez has been popular with community groups, frequently attending events in the city's neighborhoods.

In February, multiple questions from Ramirez prompted Ackerman to lash out. She ordered the commission to "reform itself."

Ackerman said her staff had answered Ramirez' queries, and that the commission had effectively "tied our hands and shackled our feet" by hesitating to do as she asked.

"It's time for reform," Ackerman said. This doesn't have to do with children. It's an adult matter."

In recent months, Ramirez has asked questions about no-bid contracts, real estate policies and teacher hiring practices.

Helen Gym, a founder of Parents United for Public Education, suggested that the move may be political.

"There's open dialogue about getting Republican representation onto the SRC," said Gym.

Ramirez, new commission chair Robert Archie, mayoral appointee Johnny Irizarry, and Joseph Dworetzky - Rendell's other nominee, who is awaiting confirmation by the state Senate - are Democrats. So is the final member, Denise McGregor Armbrister.

"It seems as though the people who appointed her gave her no back up as concerns became evident," Gym said. "It's a serious issue about accountability for the district and whether the SRC is a body of five rubber stamps or not."

Shelly Yanoff, executive director of Public Citizens for Children and Youth, said that Ramirez' shoes will be tough to fill.

"Heidi was as good as you can get – in education, in community, to kids, a model for what you want in a member" said Shelly Yanoff, executive director of Public Citizens for Children and Youth. "She believed that public accountability was the role of the SRC."

Ramirez, the first Latina to serve on the panel, was first nominated in 2007 by Rendell to fill an unexpired term.

She has cited early childhood education, teacher quality, and the education of English language learners as issues especially important to her. At today's commission meeting, she cast the lone "no" vote of the day, on a measure to allow actor Tony Danza to teach and film a reality show at the district's Northeast High.

Contact staff writer Kristen Graham at 215-854-5146 or kgraham@phillynews.com.