Number of questions
In the past, I would have a teacher that would give one or two questions quizzes and even final exams! To me, this was an extremely unfair assessment of what I learned in the class and gave me even more anxiety about the test(s). To me the absolute minimum number of questions is 10. I use at least 20 for the quizzes and at least 50 for the final. This is the only way to determine a fair assessment of the students' abilities.
We have found that by having a min. of 20 question quizzes, the students felt more at ease in that they had a better chance of passing. Some other quizzes have 25 with our final at 50 questions. Also, we have incorporated take home quizzes that parallel the others so that even though to the student it appears that there are a number of tests to take, they all cover essentially the same subject matter. This improves retention and overall course evaluations.
I agree that more questions will give us a better idea of the syudents comprehesion but I think some students will get stage fright if they see 2 or 3 pages of questions.
Yes, the big number theory applies here. The more questions will show the true percentage of learning from the course content. If they got zero out of two questions wrong they have have gotten the next eight right if they existed, or even scored a sixty or a seventy. Zero percent does not accurately portray the student's knowledge.
