8 February 1999 Vol. 4, No. 6
THE MATH FORUM INTERNET NEWS
Sketchpad for Little Ones  FAQs: Proofs, Formulas  Triumph of the Nerds
SKETCHPAD FOR LITTLE ONES  Geri AndersonNielsen
http://mathforum.org/sketchpad/littleones/
The Geometer's Sketchpad (GSP) is a powerful tool for
discovering geometric properties. The program contains
a ruler, a protractor, a calculator, and a simple word
processor, in addition to graphing possibilities for
the Cartesian plane.
The activities illustrated are samples of those used
in the Lower and Middle School mathematics classes at
Georgetown Day School, and were first assembled for a
handout for presentations made at the 1998 NCSM/NCTM
Annual Meetings.
Activity Grades
Exploration all
Lines, Rays, and Segments 35
Acute, Obtuse, and Straight Angles 2
Guess the Angle 2
Area and Perimeter 3
How Many Degrees in a Triangle? 4
Circles 4
How Many Degrees in a Quadrilateral? 4
Sum of the Interior Angles of a Polygon 4
StudentMade Quiz 7
Similar Triangles 7
Transformations 7
\/\/\/\/\/\/\/\/\/\/
New from the Dr. Math FAQ: Proofs, Formulas
PROOFS
http://mathforum.org/dr.math/faq/faq.proof.html
What is a proof? How do you write a twocolumn proof?
This new FAQ from the Math Forum's project Ask Dr. Math
provides excerpts from and links to answers from the
Dr. Math archives.
For more discussions pro and con about twocolumn proofs,
search the archives of the newsgroup geometryprecollege for
the words two column proof and browse the threads returned:
http://mathforum.org/discussions/episearch/geom.precollege.html
See also these three articles from Alexander Bogomolny's
interactive monthly column for MAA Online, "Cut the Knot"
(you will need a Javaenabled browser):
 Proofs Without Words
http://www.cuttheknot.com/ctk/pww.html
 Pythagorean Theorem  includes over 20 proofs
http://www.cuttheknot.com/pythagoras/
 Proofs in Mathematics  a discussion of the value of proofs
in the classroom, followed by a collection of proofs
classified as "simple" or "charming"
http://www.cuttheknot.com/proofs/
\/
ANALYTIC GEOMETRY, TRIGONOMETRY FORMULAS
http://mathforum.org/dr.math/faq/faq.formulas.html
Robert L. "Dr. Rob" Ward has added two new units to the
FAQ area on formulas:
 Analytic Geometry Formulas cover one, two, and three
dimensions: points, directions, lines, triangles, polygons,
conic sections, general quadratic equations, spheres, etc.
 Trigonometry Formulas provide definitions of trigonometric
functions and formulas for bounds, identities, relations
in right and oblique triangles, and inverse trigonometric
functions.
\/\/\/\/\/\/\/\/\/\/
TRIUMPH OF THE NERDS: A HISTORY OF THE COMPUTER
Robert X. Cringely, PBS Online
http://www.pbs.org/nerds/
Learn how youthful amateurs, hippies, and selfproclaimed
"nerds" accidentally changed the world. This companion site
for the Public Broadcasting System television special hosted
by Robert Cringely, "Triumph of the Nerds: The Rise of
Accidental Empires," presents a tour of the history of the
computer from the abacus to the World Wide Web.
Highlights include:
 Transistors (1947)
 Doug Engelbart and the minicomputer (1968)
 Apple II (1977)
 The IBM PC (1981)
 TV program transcripts
http://www.pbs.org/nerds/timeline/
\/\/\/\/\/\/\/\/\/\/
CHECK OUT OUR WEB SITE:
The Math Forum http://mathforum.org/
Ask Dr. Math http://mathforum.org/dr.math/
Problems of the Week http://mathforum.org/pow/
Internet Resources http://mathforum.org/~steve/
Teacher2Teacher http://mathforum.org/t2t/
Discussion Groups http://mathforum.org/discussions/
Join the Math Forum http://mathforum.org/join.forum.html
Send comments to the Math Forum Internet Newsletter editors
_o \o_ __ \ / __ o _ o/ \o/
__ __/ \__/o \o  o/ o/__/ /\ / 
\ \ / \ / \ /o\ / \ / \ /  / \ / \
