NEWPORT BEACH (AP) -- Parents of some students being targeted for expulsion for hacking into computers at a wealthy Southern California public high school to access tests and change grades are charging that the cheating scandal is far bigger and district officials are whitewashing the crisis by throwing a "handful of students to the wolves."

Newport-Mesa Unified School District board members are expected to vote Tuesday on whether to expel the 11 students at the request of the principal of Corona del Mar High, the Orange County Register reported. The students are accused of hacking into the computers with the help of a private tutor who has been missing since Newport Beach police searched his home on Dec. 18.

Now, parents of four of the 11 accused students are questioning why their children have been targeted when the tutor was working with as many as 150 students.

"You cannot simply throw a handful of students to the wolves and claim that you have solved the cheating crisis," a group of three families wrote. "There are plenty more kids walking around your campus who are as guilty, if not more so, than any of the kids wrapped up in this scandal."

School officials are auditing 750,000 grades to see how many may have been altered by hackers over the past year, district spokeswoman Laura Boss said earlier this month. Boss declined to comment on the parents' complaints.

The tutor, Timothy Lai, is wanted for questioning although police have not issued an arrest warrant.

The school is located in a wealthy coastal area of Orange County where pressure to get into Ivy League schools is intense.

In 2009, officials said that 64 percent of students at the school had acknowledged in a survey that they had cheated on a test or quiz, the Register reported.

The recent scandal surfaced publicly in December after a student told administrators and police that the tutor had asked for his help to break into teachers' computers. The student gave the names of 11 other students who were involved. They were questioned by school administrators on Dec. 17 and recommended for expulsion two days later.

In an email to all students and parents, Principal Kathy Scott said a small group of students had "threatened the academic integrity" of the school.

A police affidavit reviewed by the Register indicates that although the district didn't go public with the scandal until December, there were hints of a problem months earlier.

A student told police that in the middle of the 2012-13 school year, the tutor asked him to help him place a device called a keylogger on teachers' computers. The student initially declined to help, he said, but later placed a device on a teacher's computer, the affidavit states.

He said that in April 2013, he and Lai broke into a second teacher's classroom to install a device.

The keylogger attaches to the computer and records keystrokes and allowed the hackers to discover passwords. The information was used to access online grade books, according to the district.

In June 2013, two girls were suspended after a teacher notified administrators that someone might have accessed her computer and changed grades. One of the girls told police about the tutor, but police were unable to get his name and the case was closed.

Boss, the district spokeswoman, said earlier this month that police did not have evidence to prove a tutor's involvement in June.

The police are continuing the investigation, which could still result in criminal prosecutions, department spokeswoman Jennifer Manzella said.