About 25% of our students currently use graphing calculators "on their
own"; but there seems to be little apparent advantage. A survey of all my
students last fall showed only token opposition to requiring a GC, with
about one-third strongly favoring such a requirement.
A question that I pose on exams requires students to show that a graph of
a certain function HAS a vertical asymptote AND a horizontal asymptote
(by using appropriate limits) and to FIND a relative extremum AND a point
of inflection (by examining "critical" and "supercritical" numbers). An
example might be f(x) = 2(x-1)^2/(x-5)^2 [and f'(x) and f"(x) are also
GIVEN]. Because the question already "contains the conclusions", the
emphasis shifts to justifying the "answers". Even students who can
easily use their graphing calculators seem NOT to have an advantage.
Laboratory manuals such as
TI82/TI85 GC Lab Manual by Blake _et al_ [DC Heath]
Discovering Calc with the GC by Shoaf-Grubbs [John Wiley]
Graphing Calculator Activities (...precalculus) by Lund & [Addison-Wesley]
are all very useful sources of ideas for in-class, homework projects, and
exam questions.
matthewg@goliath.sunyocc.edu
George E. Matthews, Onondaga Community College, Syracuse, NY13215
(315) 469-2381
On Tue, 16 Apr 1996, Murphy Waggoner wrote [in part]:
> The problem, however, is how to
> write an exam that is calculator independent, i.e., how does one write an
> exam so that the students with a graphing calculator do not have an
> advantage over those that do not? One response to this question is "Have
> them show their work."
[snip]
>
> Another option is to ask many concept questions and design questions that
> cannot be done or verified on the calculator (for example, in calculus the
> student could be given graphs of f' and f'' and certain points for f and
> asked to graph f). The problems with this is that there is not (yet) a
> repository for these types of questions available to the student or the
> instructor.
[snip]
> I believe more instructors would allow students to use calculators on exams
> if we could provide them with more support including test banks, better
> texts, training, etc.