FOLSOM, Calif. -- A Sacramento-area school district is now on notice it will be sued by a mother who claims she was pressured to pay for her child to perform in a school's band. The question is: Was payment required or merely requested?

When it comes to who pays for the music program at Folsom High School, one mother says the school is out of step with the law.

"My attorney has now sent them a letter, advising them the district is, in fact, responsible," said parent Donna Kinsella.

Kinsella is now fighting the Folsom-Cordova School District over invoices she has received for years that assessed dues for all three of her children to participate in the school bands.

Kinsella's oldest son, Kevin, graduated from Folsom High School. He said he remembers the pressure on students and their parents to come up with the money.

"The band director was always asking people to pay, making sure they get in the money. So, it was like, if you couldn't pay, I guess it would kind of be embarrassing," Kevin Kinsella said.

The California Education Department says the law is very clear about protecting students from being charged for a public education.

"The student cannot be charged to participate in things that are part of school activities," said Department of Education spokeswoman Hilary McLean.

But the invoices sent to Kinsella are from the school's booster group, not directly from the school. The boosters say the dues are voluntary, but Kinsella says that is not made clear in the invoices.

"Any reasonable person who looks at the invoices and newsletters that come out is going to clearly see that these are dues and not donations," Kinsella said.

Because the Folsom-Cordova School District has been put on legal notice it will be sued, it referred KCRA 3 to the boosters' organization -- a nonprofit that is separate from the school. But some legal experts say the district may not be shielded.

"If the school is trying to get around the Constitutional requirements and the Supreme Court requirements for providing free schools and free extracurricular activities by delegating that to another entity so they can do what the school couldn't do, then certainly that can pose some problems,' said Pacific Justice Institute spokesman Matthew McReynolds.

Kinsella's goal is a class action lawsuit, so parents can sue for many years' worth of dues.

"That other parents will now know that they have rights and question it when they get a bill from the school," Kinsella said.

KCRA 3 talked with the head of the boosters' organization late Wednesday afternoon. He said that they would not be able to continue the nationally recognized music program without the student dues.