If you grew up in West Africa; and/or learnt English as a second language, then the above expression isn’t strange to you.
SCHOOL
School is an institution for educating children, or where instruction is given in a particular discipline.
Having that in mind, it means that the institution does not stop to exist when school’s activities are just being suspended for a day or two.
WHAT TO SAY:
Pertaining to known public holidays, like the Democracy Day, Independence Day, Teachers Day… It is right to say:
✓There is no school activities tomorrow.
✓There won’t be any class activities tomorrow.
A situation where the school embarks on strike or the teacher (instructor) will be absent, say:
✓There will be no class tomorrow
✓I don’t have any classes tomorrow
✓Because of strike, there shall be no class tomorrow.
✓There is going to be no class tomorrow.

