normally i wouldnt tell.
once i did tell because the two girls were stupid about it. the professor left the class during the exam and the two girls decided to cheat. well they werent quiet about it and it disturbed my concentration because they were talking so loud. i wouldnt have tattled for being loud, but when i told them to please keep it down, they gave me a dirty look. so yea, i told on them because of the dirty look they gave me. if you're gonna cheat, then don't disturb others while doing it, and especially dont piss other people off.