A former Portland Public Schools teacher has filed a whistleblower and discrimination lawsuit against the district, saying she was forced out of her job for calling attention to disturbing conditions for disabled students.

Filed in Oregon District Court on Monday, former occupational therapist Christine Van Osdol says she and others were overworked and unable to provide legally-mandated care to disabled students.

In one instance, the suit says, Van Osdol saw a teacher screaming at a child with autism and "other illegal acts occurring in the classroom relating to treatment of disabled children. The lawsuit also says Van Osdol saw a room full of students with no teacher present and learned that one-half of the cases involving disabled students were out of legal requirements.

She says that when she complained, PPS officials told her to "only serve those children whose parents are litigious."

The suit seeks $450,000 in damages, and names both the district and Van Osdol's former supervisor, Linda Moon.

Van Osdol's suit comes on the heels of an arbitrator's ruling last year finding that Portland teachers were overworked and underpaid; that ruling cost PPS $1.5 million. 

Van Osdol also claims the district failed to accommodate her herniated disks in her spine, which caused her further injury.

She previously filed a claim with the federal Equal Employment Opportunity Commission in 2012, the suit says. The EEOC gave her a right to sue notice on Nov. 5.

Portland Public Schools spokesman Matt Shelby did not immediately respond to a call for comment.