Comments on: My Exponential Function Unit http://samjshah.com/2009/05/04/my-exponential-function-unit/ Tue, 15 May 2012 22:49:27 +0000 hourly 1 http://wordpress.com/ By: Math At Play Blog Carnival #7 - Onomatopoeia http://samjshah.com/2009/05/04/my-exponential-function-unit/#comment-1015 Fri, 15 May 2009 10:02:35 +0000 http://samjshah.com/?p=1324#comment-1015 [...] Shah presents My Exponential Function Unit posted at Continuous Everywhere but Differentiable Nowhere.  He asks his kids if they would rather [...]

]]> By: samjshah http://samjshah.com/2009/05/04/my-exponential-function-unit/#comment-986 Thu, 07 May 2009 00:51:53 +0000 http://samjshah.com/?p=1324#comment-986 @Kristen: we have a rotating schedule at my school. And the way it rotates, students meet for classes 4 days a week, instead of 5. And the classes meet at different times of the day, each day.

]]> By: Kristen http://samjshah.com/2009/05/04/my-exponential-function-unit/#comment-985 Wed, 06 May 2009 12:54:46 +0000 http://samjshah.com/?p=1324#comment-985 Enjoyed reading this – it gave me some good ideas for next year’s exponential functions unit in Algebra 2.

One question, though – why do you just meet 4 days/week? Just curious. :)

Kristen

]]> By: samjshah http://samjshah.com/2009/05/04/my-exponential-function-unit/#comment-976 Tue, 05 May 2009 21:28:45 +0000 http://samjshah.com/?p=1324#comment-976 @Nick: You fixed it! Wow, good troubleshooting. Thanks a zillion. It was annoying me to no end!

]]> By: Nick http://samjshah.com/2009/05/04/my-exponential-function-unit/#comment-974 Tue, 05 May 2009 02:46:57 +0000 http://samjshah.com/?p=1324#comment-974 I know why everything on your blog went italics. You put an em tag (for the italics) in this post right before the fold, but when you page normally loads, it doesn’t load the below the fold part where the tag is closed. That’s my read. Basically, close the em tag before you add the option to expand the post.

]]> By: samjshah http://samjshah.com/2009/05/04/my-exponential-function-unit/#comment-973 Tue, 05 May 2009 01:32:41 +0000 http://samjshah.com/?p=1324#comment-973 @mjs: In fact, I did that penny drop exercise (http://samjshah.files.wordpress.com/2009/05/2009-04-27-exponential-functions-applications-c14.doc) — but instead of getting the pennies, I had students run a calculator simulation. I thought we could get the same benefit, but without all the time spent counting. Plus, I wanted students to drop 100 pennies. As for the die, I actually had that as a homework problem this year!

The beer thing is new to me… looking online, there’s an IgNobel that went to it, but for some reason I can’t access the paper…

]]> By: mjs http://samjshah.com/2009/05/04/my-exponential-function-unit/#comment-972 Mon, 04 May 2009 21:28:29 +0000 http://samjshah.com/?p=1324#comment-972 little “labs” you could do for half-life data:
PENNIES
1) start with 20 pennies in a cup, shake and dump out on table. (n = 20)
2) remove any pennies that are tails. count # of heads pennies. (n = 10 or so)
3) put the n “heads pennies back in cup, shake and dump out on table.
4) remove any pennies that are tails. count # of heads pennies. (n = 5 or so)
5) repeat steps 3-4 until n = 0
6) graph data
(also try using with die, where you remove only when face value is 5 or 6… this gives a longer half-life)

BEER
supposedly, the foam head on beer “decays” more or less exponentially. i haven’t tried this yet, but a friend told me that you can have kids take data on the foam of non-alcoholic(!) beer poured into a graduated cylinder. the mL markings offer a metric for amt of foam. use a stopwatch for time. measure every x seconds. graph… calculate half-life of beer foam head.

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