Since I moved to the Bush of Alaska, I have seldom received telemarketer calls. I used to get them all the time when I lived in Colorado, New Mexico and other states. I hated those calls because they always arrived at a bad time or they were trying to sell me something that I didn't need or couldn't afford.
I got tired of trying to say no and having them ignore it. I really hate just hanging up on them, so I developed a question for them to answer in 15 minutes, I would listen to them. Usually after posing the question, I'd hear dead silence and never hear from them or the company again. I think they put me on the do not call list.
I usually asked them to solve a not too complex math problem. I simply said if they could find the fourth derivative of sec^2 theta within the next 15 minutes, please call me back with the answer and I'll listen to the sales talk. Do you know that I never heard from any sales people with the answer? That was sooo cool.
Today I"m taking a class on learning to teach writing in my math classes. I've gotten one technique I can use for my math class. Divide the students into groups and assign each group a part of the text. Have them read it, summarize the material and then write up where others can see it. Yeah. I can try it Monday.