They participate without enthusiasm. Their body language often expresses boredom. Some have exceptional ability but show undeniable signs of poor self management or bad attitudes. Others are diligent but simply average in academic ability. They have some concept of what is going on but clearly have not mastered the material.
Plagiarism is a form of cheating.
Plagiarism often results when a student turns in a paper or project without explicit acknowledgment of the source or sources of information used in their paper or project. A good rule of thumb is that when in doubt, over document your sources. Theatre by definition is a collaborative work by a number of individuals. However, do not mistake collaboration for cheating. Students are expected to perform their own tasks and assignments in the course.