I would prefer not to give multiple choice tests, however, there has been some friction over the essay/short-answer questions.
My tests are about 1/3 multiple choice, 1/3 short answer essay type questions, and 1/3 problem solving. or some combination depending on the class and material.
With the short answer/essay questions, I find the students are not specific enough sometimes. Another problem is students aren't clear. and then of course I have students who can not write a coherent sentence.
Example:
On the last test I asked students to explain the difference between a real and a virtual image.
Student answered: You can see a real image. You can't see a virtual image.
I took off points for this because it is not fully correct.
I handed back the tests and the arguing began.
I explained what the correct answer was and what were ranges of acceptable answers.
Student was like that was what I said. I responded no you left out some key point, like can be formed on a screen.
He was like well, you know what I meant. I said no I don't know what you meant. I only know what you wrote down. Student continues to insist his answer is correct enough.
I finally say if a real image is something you can see, if I close my eyes and can't see, is everything a virtual image.
But this is what happens. I give partially credit, I let things slide, and I get well you know what I meant from the students.
Tina
Tina Fanetti
Physics Instructor
Western Iowa Technical Community College
4647 Stone Ave
Sioux City IA 51102
712-274-8733 ext 1429