Is it lashon hara to tell someone in my class that the teacher is not Shomer Shabbos?
Answer:
This is not considered lashon hara, because if she violates Shabbos publicly, this is common knowledge.
However, the Chafetz Chaim writes that it remains wrong to spread such information without there being a positive purpose, and for the sake of gossiping alone.
Thus, if there is a positive reason to tell your classmate, it is permitted to do so.
Best wishes.
