Adrienne, I begin by looking at the course objective, and student learning outcomes (if they're present). For me, I want to make sure I am acuurately measuring learning. Therefore, the more important content elements in a course should have more weight. But I also realize people learn in different ways so I try to have as much variety in the grading system that still allows accurate measurement. Also, I think trial and error, past history, and institutional policies have a place. Needless to say, it has to be fair to all (one reason I avoid extra credit). Barry Westling