- From"Carol Townsend" <edu-support@xxxxxxxxxxxxxx>
- DateTue, 6 Mar 2007 17:25:45 -0600

Hey all,

This math lesson idea is still bouncing around in my head - guess once you're a teacher, it sticks, huh?

Anyway... would it be a worthwhile excercise to do something like:

a) give the kids sets of pyramids

b) have them try to figure out what the formula is for the relation of Base Size to Face Height to pip count (with all those terms defined, of course)

c) get a class consensus on this formula

d) reveal the "real" formula - and then figure out the deviation that their experimental formula revealed (ok... so I'm thinking more like a science teacher here... but that's my training... and it's a valid skill for say engineers who are more math than science based... right???)

e) extrapolate with their formula (or the "real" one that Andy just shared) - to figure out how many pips a Giant Cardboard Pyramid set would be... or the pyramids at Giza, for that matter.... or various other pyramidal solids you might have...

I really like Andy's formula, as it's involves exponential growth - something that is found all the time in nature. And by doing the "extrapolate how many pips" you're having to do logs and such. Fun! :)

For those who missed the formula, it's something like

Base Size = 4/7 Face Height = [ 4 + (2^n-1)] / 8

where "n" is the number of pips. (that's 4 plus "2 to the power of n-minus-1" all divided by 8)

Which... gets me past my math abilities at this time of night...

So... thoughts on this??

thanks!

Carol

This math lesson idea is still bouncing around in my head - guess once you're a teacher, it sticks, huh?

Anyway... would it be a worthwhile excercise to do something like:

a) give the kids sets of pyramids

b) have them try to figure out what the formula is for the relation of Base Size to Face Height to pip count (with all those terms defined, of course)

c) get a class consensus on this formula

d) reveal the "real" formula - and then figure out the deviation that their experimental formula revealed (ok... so I'm thinking more like a science teacher here... but that's my training... and it's a valid skill for say engineers who are more math than science based... right???)

e) extrapolate with their formula (or the "real" one that Andy just shared) - to figure out how many pips a Giant Cardboard Pyramid set would be... or the pyramids at Giza, for that matter.... or various other pyramidal solids you might have...

I really like Andy's formula, as it's involves exponential growth - something that is found all the time in nature. And by doing the "extrapolate how many pips" you're having to do logs and such. Fun! :)

For those who missed the formula, it's something like

Base Size = 4/7 Face Height = [ 4 + (2^n-1)] / 8

where "n" is the number of pips. (that's 4 plus "2 to the power of n-minus-1" all divided by 8)

Which... gets me past my math abilities at this time of night...

So... thoughts on this??

thanks!

Carol

- [Edu] Math teacher question - part 2 Carol Townsend
- Re: [Edu] Math teacher question - part 2 Ruth Levenstein
- Re: [Edu] Math teacher question - part 2 miyu