If I saw a friend of mine cheating on something, depending on who it was I would probably tell them not to do it.  However, in some special cases I would probably tell on them.  Also, I may not say anything at all, all depending on the specific situation.  Cheating is not good, but pretty much everyone has done it at least once in their life.  I will admit that the one time I really did it was in second grade on a spelling test, but I haven't really done it since.  I learned my lesson.  Cheating is not ethical or honest either. It can be tempting to do, but I try not to do it when I could if I wanted to.