I must've cut out a couple days' worth of assignments here and there this semester, because when I planned out the rest of the semester for my pre-calculus classes today, I had 4 "extra" days of instruction that I haven't had in years. And I know just how to spend those 4 days--logarithm boot camp!
I'll be lucky if I can recreate this LBC experience.
If you need a little bit extra for your logarithm plan, I recommend sound level to decibel conversion.
ReplyDeleteStudents suspect that trigonometry and the quadratic formula can be useful, so they aren't too surprised when they are expected to use those to solve problems in physics. When logarithms show up for calculating decibels, students think that I'm screwing with them or just telling them a little enrichment activity.
Students have heard of decibels and the conversion isn't complicated. Even though the calculator does all the work, they need to do a couple of practice problems to reacquaint themselves with the log and inverse log functions.
Since you know how logs work, it isn't hard to do them in your head. The third practice problem, I have a student suggest a sound level, and I announce that I have an answer in a couple of seconds. It really takes about 30 seconds, but by the time the student has written it on the board, I've got it.
These are good students who aren't confident that they've got the answer using a calculator, so they look at me like I'm a wizard. Once they are convinced that it isn't a trick, they are in awe. Doesn't hurt for them to finish the year thinking I'm a genius.
I don't wait till the end of the year to have my students think I'm a genius :-)
ReplyDeleteWhen we first covered logs, we did problems including W/square-meter to dB as well as Richter Scale conversions (we are, after all, in California). My Logarithm Boot Camp includes going back to tables, getting students to grok logs as opposed to merely knowing how to get a number out of a calculator, and then having students come up with "interesting" problems for they and their classmates to solve. Every time I ever taught this I would have students ask, "Why didn't you teach it like this the first time?" There are myriad answers, including "You wouldn't have appreciated it then, as you didn't know how little you truly understood logs" and "This isn't how I'm supposed to teach it, this is enrichment after you have a basic understanding." TBH, if I *had* taught it like this originally, they probably would have done better originally and wouldn't need this enrichment now, but whatever. They'll get the instruction now.