In a statement yesterday, Superintendant Dr. Christopher McGinley confirmed that the laptops indeed have a "security feature" to track missing systems. The "feature" can take a "still image of the operator and the operator's screen," but McGinley said it has been deactivated, and will not be reactivated without express written notification. He also insisted that the feature has only been used to locate lost, stolen or missing laptops.
Students involved in the suit have contacted Gizmodo with details about the situation. It's said that the green lights next to the kids' laptops often turns on, suggesting it's in use, but the district claims it's just a glitch. One student questioned a school IT guy about the light, who said it was occurring because "people logged out when an application using the camera was on." The employee also admitted that the school could in fact look through the webcam, but it would violate law.
You can read more about the Robbins v. Lower Merion School District suit via this PDF.