LA MESA, Calif. -- The Grossmont Union High School District board was expected to consider Thursday night taking the first step toward revoking Helix High School's 11-year-old charter because of how the school handled a recent series of teacher sex crimes, it was reported Thursday.

Superintendent Robert Collins said he will make the case to the board that Helix has failed to improve its governance and policies since the scandals broke, The San Diego Union-Tribune reported.

Four former Helix teachers were convicted of sex crimes involving students between December 2006 and September 2008.

Collins said the La Mesa school failed to follow laws for reporting abuse and that it would allow teachers to interact with students under a "staff-student interaction policy" that he believes is too liberal, the Union- Tribune reported.

Though charter schools are self-governed, they must have the approval of a public school district to operate because they receive state funding.

Since the scandals, Helix officials have staged workshops to train staff to recognize and report abuse, charter spokeswoman Jennifer Osborn told the Union-Tribune.

The charter also tightened its policy regarding what constitutes acceptable student-staff relationships. Unacceptable behavior outlined in the policy includes unnecessary physical contact in private, intentionally being alone with a student away from school, sexual jokes or comments, and forming an emotional tie with a student for an employee's benefit.

Osborn said she suspects the district wants control over Helix for financial reasons, according to the newspaper.

Collins told the Union-Tribune that Helix is run by a board consisting mostly of parents, employees and former employees who are too close to the school to provide objective governance.

The Grossmont board is scheduled to meet at 6 p.m. at the East County Regional Education Center, 924 E. Main St., in El Cajon. The meeting is open to the public.