Cheating

How should a teacher respond to cheating? Should all forms of cheating be treated in the same way? What cautions should a teacher keep in mind before accusing a student of cheating?
I have delt with forth grade students copying answers off of tests and "tracing" or "copying" artwork which is a form of cheating in art. I try and keep mobile in my room so it limits the time a student has to cheat. I will usually ask the student quietly if they were copying another childs' work. This usually gets them to be aware that I am paying attention to them. If the student continues to cheat I ask them if they need clarification on a question and sit them in a spot away from other students. This not the way I have had are delt with all forms of cheating. Another form of cheating I have had is when I have given a final art project for the students to do and one of the students turned in another students project that was from the high school. I noticed the name on the piece of art and asked the child why the name of that student was on their suppossed artwork. The student responded that their cousin was helping her make it. I investigated further and found out that the shop class had this project earlier that year and the high school student had already received a grade for it. I asked to talk to my elementary student and explained the situation. She cried and said that he did help her and wouldn't admitt any wrong doing. I asked her to write a paper on what she did and what her cousin did for proof that she knew the process. She never turned the paper in and got a failing grade. I knew that if I didn't give her on last effort to tell the truth or prove to me that she was right, that I would be in trouble. Sometimes teachers have to investigate instead of deciding on the spot if the student should be failed. I think if teachers keep their eyes open and give the students a chance to redeem (or convict) themselves, children will come to the correct conclusion and realize that cheating is not the answer.