### I Hate Teaching Probability

In my gen-ed class I'm scheduled to spend about a week (four class periods) teaching probability. I hate teaching probability.

I have no idea how to get through to my students that just because there are two options doesn't mean that the probability is 50-50. I can trip them all up by asking: "It could either snow in Miami in July or not snow in Miami in July. Estimate the probability that it will snow in Miami in July." Instead of saying 0 they would say 1/2. Even with a less ridiculous question: if you toss a thumbtack, it can land point up or point down; if you have a medical test done, the results can be correct or they could be inaccurate; if you roll a die, you could roll a 6 or you could roll something other than a 6. All of these: 50-50 in my students' minds. No matter how many examples we do. No matter how many experiments we do.

With this complete lack of intuition and their inability to do even the most basic calculations, it's sort of a lost cause. It's hard to teach probability to people who can't do arithmetic with fractions.

I'm thinking of converting two of those days into more time spent on geometry-topology (based on the Shape of Space materials). One more will get rolled into my public health and public policy topic. The fourth? I'm thinking of doing more review before the exam.

(ps. I think I caught the respiratory infection that both my parents had. Slept all afternoon, and I'm getting a cough.)

I have no idea how to get through to my students that just because there are two options doesn't mean that the probability is 50-50. I can trip them all up by asking: "It could either snow in Miami in July or not snow in Miami in July. Estimate the probability that it will snow in Miami in July." Instead of saying 0 they would say 1/2. Even with a less ridiculous question: if you toss a thumbtack, it can land point up or point down; if you have a medical test done, the results can be correct or they could be inaccurate; if you roll a die, you could roll a 6 or you could roll something other than a 6. All of these: 50-50 in my students' minds. No matter how many examples we do. No matter how many experiments we do.

With this complete lack of intuition and their inability to do even the most basic calculations, it's sort of a lost cause. It's hard to teach probability to people who can't do arithmetic with fractions.

I'm thinking of converting two of those days into more time spent on geometry-topology (based on the Shape of Space materials). One more will get rolled into my public health and public policy topic. The fourth? I'm thinking of doing more review before the exam.

(ps. I think I caught the respiratory infection that both my parents had. Slept all afternoon, and I'm getting a cough.)