SARASOTA -- The Sarasota County School District is trying to decide whether to investigate former Heron Creek Middle School Principal Scott Wilson, who abruptly resigned last week.

School district officials say they are looking into a complaint they received late on Monday.

They would not disclose what the complaint was about or who filed it, saying it could be part of an investigation.

Wilson submitted his resignation last Wednesday, citing health reasons.

Superintendent Gary Norris said he had no other reason to believe at the time that there was anything else influencing Wilson's decision.

Wilson, 44, did not return calls on Tuesday seeking comment.

Norris and assistant superintendent Lori White said they had not yet contacted any other authorities, like the police or the state Department of Education.

The school notified parents last week about Wilson's resignation with its automated phone system.

Wilson had been with the district since 2002, and was named principal at Heron Creek when it opened the following year.

Before coming to Sarasota, Wilson was the principal at a Kansas City, Mo., middle school for four years.

He had also served as an assistant principal and a teacher in the Kansas City area since the late 1980s.

Teachers and administrators here applauded Wilson for his dedication and work to improve state test scores.

He has been praised for starting the school's "community of caring" character education program.

During the 2004 school year, 60 percent of teachers at Heron Creek gave Wilson a favorable midyear review. They nearly gave him a perfect score on his "nonconfrontational disciplinary philosophy."

Former Heron Creek teacher Cheri Dennen said she was shocked to hear about Wilson's sudden resignation.

"He was an excellent principal and great to work for," Dennen said. "He brought the school some great achievements."

The complaint against Wilson comes just months after the School Board changed its policies to intensify the background checks it does on new teachers.

The changes came after the district learned it unknowingly hired a principal with a history of child abuse.

The district now asks more questions of job references, conducts Internet searches and checks with the state Department of Education to see if the prospective employee has been in trouble in other districts.

Applicants will also be asked if they have resigned in lieu of being fired, or reported to the state education department.

But the new rules would do little to govern an employee currently working in its schools.

The district is advertising for a new principal at Heron Creek.

Former Heron Creek principal subject of criminal investigation