Adventures in teaching

Late last week, some parents whose children study in the Kendriya Vidyala approached one of the student bodies in IISc. The parents said that some teachers were away for a couple of weeks on paper correction duty, and asked if some students from IISc could volunteer to take a few classes. There was no need adhere to any syllabus, and the idea was to just trigger some ideas in their minds, and nourish the spirit of scientific enquiry. Around 30 of us volunteered, and I spent an hour with Class 9 students today !

I decided to talk about recreational math, an area popularised by Martin Gardner in his articles in the 'Scientific American'. I am firmly of the opinion that recreatrional maths should be made a part of the mainstream school curriculum, and am sure it would greatly help motivate students to study maths. So, I picked some relatively simple, yet interesting problems that involved math/logic in some form. Some students were very enthusiastic, and came up with lots of interesting ideas. I'll reproduce here, the content from the discussions that ensued after a couple of questions -

1) I posed this problem - Anand stays in the tenth floor in an apartment complex. Each evening, after getting home from school, he uses the lift to get to the fifth floor, and then climbs up the next five floors. Why ?
                 
               After a while, the students figured out that Anand was rather short, and only could reach up to the button corresponding to the fifth floor. I then asked them what he could do to solve this problem. I got a range of solutions. One said Anand ought to carry an umbrella with which he can tap the 10th floor button. Another said he could climb up a stool( meant for the absent lift operator) and press the button himself. Someone then proposed that Anand should ask the watchman to help press the button. This was immediately followed by several answers, which replaced the watchman with a van driver, auto driver, bus driver, and the likes :-) Meanwhile one student helpfully suggested that Anand should have more complan :-) I wanted as many of them as possible to open up, and offer their opinions, so I let this go on for a while:-) Eventually, to bring it to a logical conclusion , I suggested that Anand should probably move to a flat on the fifth floor, which I admit was rather lame:-)

2) Another problem involved Harry Potter, and his wand, except that they were on the two sides of a river. "How can Harry get hold of his wand?" was the question. There were a few other details I included such as the width of the river, and the length of the blocks of wood, which were available in plenty, but that weren't long enough to help get across the river. The students however, chose to ignore these details, and came up other innovative answers to help Harry :-)

One immediately responded saying Harry could use his broom to get across ! So ofcourse, I barred the broom usage, which led one to suggest that Harry should swim aross. To make it interesting, I introduced some crocodiles into the river. The student however persisted with his swimming approach, and suggested that Harry ought to use his magical powers to defeat the crocodile, and then swim across. Meanwhile, another pondered over the possibility of taming the crocodile, and asking for its help ! Of course, we were really quite far from the problem statement, but I didn't really care. The students were earnestly trying to think up solutions to solve Harry's problem, and were enthusiastic in their responses !

There were a few other questions, which they actually did solve, somewhat to my pleasant surprise. As I walked out of the class at the end of an hour, I could hear some students jubiliantly yelling 'Yay', but a couple of minutes later, two students followed me outside, and shyly said ' nice class!', so needless to say, I was thrilled ! All in all, it was definitely an interesting experience !