Donna Hathaway-Beck, one of the longest-serving members on the Prince George’s County Board of Education, submitted her resignation Wednesday, the second member of the newly reconfigured board to quit in less than two months.

Hathaway-Beck (District 9), whose resignation will take effect Sept. 6, said work on the board was taking too much time away from her family. She has served on the board for nearly seven years.

“For over 20 years much of my life has been dedicated to public service in Prince George’s County,” Hathaway-Beck wrote in an e-mail to her colleagues. “I am ready to start the next chapter of my life, spending more time with my husband, Don, our four children and four young grandchildren.”

Hathaway-Beck’s resignation comes as the county’s school system undergoes major changes in leadership, the result of County Executive Rushern L. Baker III’s plan to turn the system around. During the past several months, four new appointed board members have been sworn in and a new schools chief hired.

Hathaway-Beck said she supported Baker’s effort but disagreed with his tactic of pushing a bill through the General Assembly in the final weeks of the legislative session. She said Baker’s move was not a factor in her decision.

In addition to wanting to spend more time with her family, Hathaway-Beck said, the decision to resign more than a year before her term ends was based in part on the confidence she has in Kevin M. Maxwell, the new chief executive of the schools.

“I was encouraged by the naming of Dr. Maxwell,” Hathaway-Beck said. “It gave me the peace of mind that I needed.”

Hathaway-Beck, known as a government watchdog, was part of the new school board elected in 2006 after the former board, which had been appointed, was dissolved. She ran for office after recording what she said was perfect attendance at school board meetings for nine years.

“She’s definitely a staunch advocate who speaks her mind and comes with a nonpartisan approach,” said Segun Eubanks, chairman of the school board.

Hathaway-Beck’s departure opens the door for Baker (D) to have even more influence over the school system. Under a new state law, Baker has the power to name appointees to fill board vacancies.

Carletta Fellows (District 7) resigned in July, citing personal reasons. Her decision came a day after the school board, during an executive session meeting, discussed her background check and unauthorized credit-card purchases, according to two sources familiar with the proceedings.

Baker announced Wednesday that he plans to fill the District 7 seat with Lyn Mundey, a Bowie High School alumna who lives in Upper Marlboro and is the mother of a seventh-grade student.

A graduate of the University of Maryland, Mundey is a management analyst for the U.S. Government Accountability Office.

Christian Rhodes, Baker’s education adviser, said Mundey will complement those already on the board, bringing a number of important perspectives from her multiple connections to the school system.

“She represents a different voice,” Rhodes said.