The total score will be computed in a way that allows students not to count one weak performance. In particular, the total score will be computed as the top 4 scores among 5 parts, each weighted equally. The two midterm exams each count one part; the final exam counts two parts; and the homework counts one part.
In order to have a fair meaningful allocation among the five parts, the score on each part will be computed by scaling, in particular, by dividing the individual part score by the class mean on that part. Thus, if you scored 90 on a midterm for which the class mean was 60, you would earn a score of 1.5 on that part. The total score will then be the sum of the top 4 scaled part scores. Since everybody benefits from omitting the lowest part score, the class average total score tends to be about 4.15 instead of 4.00. Final letter grades are awarded on a curve based on these total scaled scores.
This scoring scheme provides some flexibility. For example, it allows students to elect to do no homework at all or not take one midterm exam, but the scoring scheme imposes some penalty for doing so. Students are strongly advised to do all homework and attend all exams.
Because of this scoring scheme, there will be no make-up midterm exams. If for some reason, a student must miss a midterm exam, then that will be the part that is not counted.