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Re: Calculators in classrooms
Posted:
Oct 6, 1999 6:34 AM


I'd be careful about this. Different calculators respond differently to the use or nonuse of grouping symbols.
Joan Reinthaler Sidwell Friends School
On Wed, 6 Oct 1999, Kevin J. Maguire wrote:
> Good morning, > I have been reading with interest the past correspondence on the use of inexpensive calculators in school classrooms. Together with a group of teachers in an elementary school we have devised a particular lesson on the 'Order of Operations'. This lesson depends upon the use of nonscientific calculators to force children to realise that the order in which operations are carried out is important. As an example enter the following calculations into a calculator: 3 x 4 + 6 and 6 + 3 x 4. Without the use of parentheses the solution to both equations is 18. However the nonscientific calculator will give 36 as the solution to the second equation .By presenting a series of word problems that the children could easily calculate solutions, we use the calculator to get them to confront the differences between the logic of their solution with that (in the case of the second equation) of the calculator. I cannot adequately describe the look of incredulity on the faces of some of the students when the calculator gave a solution which they knew was incorrect. Without the use of calculators this moment would not have occurred. > Kind regards, > Kevin > > Kevin J. Maguire > Ph.D. Candidate > Graduate School of Education > La Trobe University > Bundoora > VIC 3105 > AUSTRALIA > >



