I have had many students try to cheat in class and I will call them out of the room in my office hours and explain it was visible to me they were cheating. I have learned over time and years to separate students as well as scramble all paper quizzes and never let anyone talk or leave room during any of the quizzes or exams. We have cut down on homework per say as many were doing it all and others were not. I caught one whole class my first year in Medical Terminology making a word up for a fill in the blank question that doesn't even exist. I asked the whole class this question, "The first student that can find that word in the book gets a prize." Little did they know at first I had them on it and they all learned a quick lesson as to do their own work.