Here is my advice to students who need to ask their professor for a letter of recommendation. Ask your professor nicely and politely. You do not have to ask the professor in person, but do not ask the professor in a quickly jotted, informal email in all lower case! Early, early, early. It takes time…
Category: Teaching
Definition of continuity video
Thank you to Dansmath for turning me on the website xtranormal. It allows you to create your own animated videos. It is easy and fun. You can choose the characters, the scene, the camera angles, the gestures and facial expression, music, etc. They do the voices for you—you just type the script. Here are some of Dan’s videos….
Materials for a knot theory class
This is a call for help—or for suggestions, at least. I’m teaching a knot theory class next semester. I’m looking for good props to use in the class to make knots. I would like to be able to make knots such as the following (and have my students do so as well). I suppose the…
How to curve an exam and assign grades
We have all given exams where the grades end up lower than we hoped. A curve is in order. How do we do it? In this post I share my thoughts on when you should (or should not) curve an exam. I give ten sample curving techniques, including pros and cons of each, I explain…
Multiple choice questions in mathematics
It must be exam time. Discussions of multiple-choice test questions are in the air. Terrence Tao has a nice post about multiple choice questions in mathematics (it is a follow-up to this post of his). He writes about the pros and cons of giving multiple choice questions in a mathematics class. For example: These quizzes give a…
A solution for tight budgets?
All educators face challenges during these troubling economic times. The USA Today has an article about one teacher’s solution: Ads on tests add up for teacher.
Euathlus and Protagoras
In my Discrete Mathematics class we discussed a few famous paradoxes, such as Russell’s paradox/barber paradox/librarian paradox, the liar’s paradox, and the naming numbers paradox. Afterward, a student of mine shared with me this old legal paradox featuring Euathlus and Protagoras. Euathlus wanted to become a lawyer but could not pay Protagoras. Protagoras agreed to…
Thoughts on how to teach induction
In their article “Some observations on teaching induction,” (MAA Focus, May/June 2008, pp. 9–10) Mary Flahive and John Lee give tips on how to teach induction. For a variety of reasons, they encourage professors to downplay proofs of theorems such as the “baby Gauss” formula for all . Indeed, I have noticed that students can…
The prime number theorem in Calculus II
I attended Shahriar Shahriari’s MAA Minicourse Beyond Formulas and Algorithms: Teaching a Conceptual/thematics Single Variable Calculus Course at the 2008 Joint Mathematics Meeting. He talked about having his calculus students derive the prime number theorem. Recall that the prime number theorem states that if is the number of primes less than or equal to ,…
Do you give partial credit? How to grade Venn diagrams
Suppose that on an exam you asked your class to shade the region corresponding to in the figure below. The problem is worth 5 points. The correct answer is: When you received their solutions, some students had regions shaded that shouldn’t be shaded and left regions unshaded when they should be shaded. My question is:…
David Richeson: Division by Zero 