Friday was the last day of school for Henry Rubio, the principal of A. Philip Randolph High School, but he’s leaving behind more than just memories.

Two weeks ago, Rubio announced to his staff that he was resigning as principal after five years at the school to take a job with the Council of School Supervisors and Administrators. We reported that an open investigation into fraudulent credit accumulation at Randolph under his watch was closed. But it turns out that the information came to us – inaccurately – from a spokeswoman for the principal’s union.

An investigation into Rubio concluded on Thursday and found no evidence of wrongdoing on his part, according to Chiara Coletti, a CSA spokeswoman. She said the union had waited until Rubio was cleared of suspicions before giving him the job, as a member of the union’s “supervisory support panel” that helps the Department of Education mentor principals. A prerequisite for that job, Coletti said, is that candidates must be “standing principals,” and the investigation had put Rubio’s status temporarily in jeopardy.

Since then, we’ve confirmed that no investigations have been closed with the office that is probing the school, the Special Commissioner of Investigation. Today a SCI spokeswoman confirmed that an investigation is still very much open at the school, but declined to comment further on the case.

In addition, teachers I spoke to this afternoon at the school said that investigators have been regularly visiting the school over the past two weeks, most recently to review student transcripts.

In response, Coletti maintained that the union’s grievance department was initially “told that all investigations were closed,” but she added that Rubio informed union officials this week that an investigation was open.

The investigation was prompted this summer by whistle-blowing teachers who were outraged by what they said was a clear abuse of the school’s online credit recovery program, Aventa. Dozens of failing students were allegedly awarded credits for doing little work in order to be eligible to graduate. The school’s erratic graduation rates in recent years seems to support their complaints. In 2010, graduations jumped from 56 percent to 86 percent, then sank to 71 percent last year.

Today, students at A. Philip Randolph were largely indifferent to the news that it was Rubio’s last day. Several students I spoke with said that they barely saw Rubio and rarely had direct interaction with him. One student said he had seen Rubio three times all school year.

It remains unclear whether or not Rubio was pressured to resign or did so on his own accord. Rubio declined to be interviewed.