
Re: 5th graders create advertisements on computers
Posted:
Aug 6, 2000 6:33 PM


At 12:12 PM 8/6/00 0600, me@talmanl1.mscd.edu wrote: > >I don't know a mathematically literate person who disagrees with the last >with the last two of Wayne's statements above.
Well, my computer seems to have eaten my response based on one mainline publisher, so I'll use another. This one is Book 3 of a middle school curriculum that includes lots of names but the first five, and in larger font size, are Randall I. Charles, John A. Dossey, Steven J. Leinwand, Cathy L. Seeley, and Charles B. Vonder Embse. From P. 370 [with a picture of a New England farmstead] we have, "A number that cannot be expressed as a repeating or terminating decimal is an *irrational number*. Not mentioned is why there needs to be a new definition at all, since rational numbers already exist, and why the new definition is not the negation of the other. This definition is then followed by:
Example 2 Use your calculator to determine whether each square root is rational or irrational. a. sqrt(723) b. sqrt(256) Enter 723 [sqrtkey][+/]. 26.88865932 sqrt(723) is irrational.
The following exercises are just as inspired along with more irrelevant pictures; e.g., a cabbage seed splitting open.
The other book had similar problems, such as discovering that sqrt(1.21) is rational, from the calculator of course, whereas it did not have the calculation that mine gives of sqrt(1.21 + pi/10^80) which has exactly the same display; i.e., no superfluous zeros, simply 1.1.
This book doesn't have the list of such wellknown names but inside the front cover it touts its teaching package as "Uniquely developed to help you implement the NCTM Professional Standards for Teaching Mathematics" and that it is "Complete with intext correlations to the NCTM Curriculum and Evaluation Standards."
I did not invent this absurd calculator misuse nor did Milgram and Klein.
Wayne. 
At 12:12 PM 8/6/00 0600, me@talmanl1.mscd.edu wrote: >Wayne Bishop wrote: > >> Let kids check their decimal arithmetic on a calculator? Sure, I even >> tell her to but she usually doesn't. Noting that pi, sqrt(2), and >> 111/113 are irrational because the screen doesn't indicate a repeating >> pattern? Get people who push for such idiocies out of the decision >> making process. > >I don't know a mathematically literate person who disagrees with the last >two of Wayne's statements above. > >> Don't even mention the words if the kids aren't >> familiar enough with the (and it is *the*) division algorithm to be >> helped to understand the joke. > >I've currently been mulling over a paper, written by Klein & Milgram, >and titled "The Role of Long Division in the K12 Curriculum". It's a >very interesting combination of good mathematics and bad polemicsthe >latter including rationalizations and even baldly false statements. >It's available at > > http://math.Stanford.EDU/ftp/milgram/longdivision/longdivsiondone.htm > >I'd be interested in other folks' take on this note. > >Lou Talman >

