You spew some ignorant crap like this, and wonder why people don't speak up? Calling frightened and embarrassed children who have been victimized and sexually abused and exploited by a trusted adult (teacher) cowards, or accusing them of not having proof that they were victimized, is the EXACT reason these kids do stay silent.
Can you imagine the amount of courage it took for these kids to come forward and tell an adult they were victimized by this man? Can you imagine the embarrassment and possible guilt or shame they may be dealing with? That's what these child molesters do, they groom and condition these kids to keep their mouths shut.
I hope none of these kids get on this site to read any of the comments you made. When people don't come forward and speak up, it is because they don't want to have to face people with your attitude. If parents or other adults were reluctant to come forward and make these accusations or claims, it is also out of fear of their children not being believed, or "lack of proof".