Due Process: CAN DUE PROCESS BE A CLASS ACTION?

I believe not, I thought that the IDEA specifically says that Due Process is limited to one child. However, one can go after the folks who are supposed to be supervising the administration of the IDEA. This is the approach of the Concerned Parents of California, who are suing the California Department of Education for failing to monitor schools and respond to failures of the schools to follow IDEA.
Possibly you have heard of the recent concerns over the Concerned Parents of California getting data on students. As I see it, the reason for asking for access was to prove that CDE was not monitoring its own data (which might show non-compliance with IDEA), and the reason for the PII being in the data is that CDE is refusing to redact it.