Basically, the mentioned teacher gave zero on un-submitted assignments despite the school "no-zero" policy!
To me the "no-zero" policy is insane, if a student doesn't do an assignment or an exam, the teacher is supposed to either give more time to the student or simply ignore it when calculating his grades.
the story in more details :
Zero-grade teacher contemplating retirement | Canada | News | Toronto Sun
This guy should be getting an award instead of facing termination hearings!