A FORMER Philadelphia high school principal has turned in his credentials over his alleged involvement in widespread cheating on standardized tests.

Arthur "Larry" Melton, who led now-closed Bok Technical High School, surrendered his teaching and administrative credentials on July 17 due to allegations that he "violated the integrity and security of the PSSA exams for multiple years," according to a notice from the state on Tuesday.

Test scores dropped sharply at the South Philadelphia school between 2010 and 2012, the first year the district implemented new testing procedures. In 2010, 71 percent of students scored advanced or proficient in math, compared to 45 percent in 2011 and 26 percent in 2012. Reading proficiency rates fell from 53 percent in 2010, to 36 percent in 2011 to 32 percent in 2012.

Melton, 70, retired from the district in 2012, and the school was closed the following year. He could not be reached yesterday for comment.

He is not the first Bok staffer tied to the cheating scandal. Last year, Ronald Paulus, Bok's testing coordinator, briefly surrendered his teaching credential.

A state-commissioned analysis of tests in 2009 showed statistically improbable scores and suspicious erasures at 53 city schools and several others across the state. In 2011, the state launched an investigation of 14 schools, including three charters, while the district probed 19 schools.

Seven Philadelphia principals have been implicated. Deidre Bennett, Michelle Burns and Marla Travis-Curtis were fired by the district in January and recommended for revocation. Barbara McCreery and Lola Marie O'Rourke surrendered their credentials last year. Evelyn Cortez was among five educators from Cayuga Elementary criminally charged in May and terminated by the district.

The district and state are pursuing sanctions against 131 other current and former district employees as a result of the probe. State Attorney General Kathleen Kane's office is involved, and additional charges are expected.

On Twitter: @ChroniclesofSol