Final Grades

The final exams are graded in Calc II, and the scores totalled. The scores on the finals were pretty bad. The mean and the median were both 11% lower than the mean and the median on the previous exams. Ouch! There are a couple of obvious contributing factors. Calc II tends to be a hodge-podge course. It doesn't tie together as well as some other math courses. So it's easy for the students to forget things from early in the semester. The final also had a tendency to combine two or three different ideas in one question, so if I student had problems with even one of them, they did poorly on that question. Next semester, I'll have to anticipate that better, and give them more questions like that during the semester. I also think that I graded the final pretty harshly. I think I tend to feel more free to be harsh on the final, knowing that I'm not going to have to defend my scores to the students. Which is totally unfair to the students, of course.

So, anyway, I decided to adjust the scores on the final exam. Basically, I simply added about 11% to everyone's grade, to bring the scores into line with their previous exam. I think that that's reasonable. There didn't seem to me to be any evidence that the class as a whole really was worse at this material than they had been all along.

Of course, I kept track, and the bonus didn't change that many grades. It helps that my university has a five point grading scale: A, B, C, D, and F. No plusses, no minusses, no half-step grades. That means that each grade is pretty damn broad. This can be a problem when you are trying to motivate people for the final. I had a student in last week to check what he could potentially get in the class. He was sitting at 85%, so basically to get a B, he needed to score between 63% and 114% on the final. Not a lot of reason for him to break his neck trying to do his best on the final. If I had a B+ or an A- to dangle in front of him, it might help.

The one group that was strongly affected by the bonus was the A's. Going into the final, I had three people who had A's, and all of them dropped to a B using the straight final score. All of them bounced back up to an A when I gave the final bonus. And that seems reasonable. They did relatively badly on a straight scale on the final, but they were still the best students in the class.

One other student who was affected was a student who just went into free fall at the end of the semester. He had started as a borderline A/B student, then slipped to a solid B. Then he did really poorly (a D, I think) on the fourth exam, and simply bombed the final. He had several questions that he just left blank. With the original final score, he dropped to a C, but with the bonus, he held his B. I feel a little bad about that. When you bomb the final that badly, it should affect your grade. On the other hand, I know that he's a bright guy and a good student. It's likely that he had some sort of personal issue that distracted him for the last month or so. Anyway, I'm going to go with the B, because it stays consistent with the way I'm grading everyone else.

None of this is quite decided, yet. I always like to leave my final grades for at least 24 hours before committing to them. So I haven't posted them, and I haven't turned them in to the registrar. I'll look at them again tomorrow, and see if that's what I want to do. I'll want to check the highest B's and the highest C's and the highest D's, to make sure that they shouldn't be bumped up.

And everyone thinks that math is such a subjective area!

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