
A Tour of GeoGebra
Award Winning Free Software for
Visualizing Math

Calgary
City Teachers' Convention
February 15, 2013
Glen Reesor






A Tour of GeoGebra
 Sightseeing tour with a little bit of handson
 GeoGebra features and constructions for typical high school math
 We'll just be scratching the surface of GeoGebra's
capabilities
 Please ask questions during this presentation




What's This “GeoGebra” Thing?
Part 1
Classroom Example 1: Domain and Range
 So straight forward, yet...
 How about a graphical approach?








Classroom Example 2: Sine Law
 Manipulate the equation
 Understand the geometric implications








Classroom Example 3: Sine Law Ambiguous Case
 Show students dynamically that it's a result of specifying two sides and a noncontained
angle








What's This “GeoGebra” Thing?
Part 2
 "GeoGebra is free and multiplatform dynamic mathematics
software for all levels of education that joins geometry, algebra,
tables, graphing, statistics and calculus in one easytouse package."
 Created by Markus Hohenwarter as part of a Master's
and
then PhD
in Math Education at University of Salzburg (2001), then continued at:
 Florida Atlantic University (2006  2008)
 Florida State University (2008  2009)
 Johannes Kepler University (Austria) (2009  Present)
 Now developed by Hohenwarter and a team of opensource
contributors around the world




 Some supporting institutions:
 Google Summer of Code (2010  2012)
 Austrian Ministry of Education
 University of Luxembourg (2005  2010)
 Department of Math Sciences, Florida Atlantic University
(2006  2009)
 Austrian Academy of Sciences
 Department of Math, University of Salzburg
 Free Software Foundation, Hungary




Today's Plan
What's This Geogebra
Thing (Cont'd)
 Hands On: Points, angles, functions, sliders, and more

10:45  11:15


Educational Scenarios
 Demos, activities, animated solutions, mathematical
justifications, multistep constructions, picture creation, upload to
website

11:15  11:30


Playtime!
 Play with GeoGebra
 Investigate others' constructions

11:30  11:50


GeoGebra is wonderful because...

11:50  12:00





Hands On
Inscribed Angles
 Points
 Line segments
 Angles
 Circles
 Arcs









Investigating Cubic Functions
 Functions
 Sliders
 Points
 Color
 Size








Educational Scenarios
 Demonstrations
 Activities
 Animated problem solutions
 Mathematical justifications
 MultiStep constructions
 Picture creation
 Upload to website / Learning Management System (Moodle,
WebCT, etc)




Demonstrations: Parallel Lines and Transversals




Activities: Parameter Exploration




Animated Solutions: Vector Addition




Mathematical Justifications  Horizontal Translations




Mathematical Justifications  Horizontal Translations (Take 2)




Multistep Constructions
 GeoGebra isn't limited to the builtin commands.
 How would you create a parabola given the
vertex and one point?
 Just do the math...












What a mess. Does it work?




Picture Creation
 Use GeoGebra to create beautiful, correct pictures in multiple formats (svg, png, emf, pdf, eps)




Upload to Website
 Your constructions will be completely selfcontainedno
need for students to download / install any software
 Scenarios
 Shared drive in computer lab
 Learning Management System (Moodle, WebCT, Desire2Learn
...)
 School / Personal website
 www.geogebratube.org




Play Time!
 Install GeoGebra using the geogebra.org installers
 When you think of using GeoGebra, are you a Finder or a Creator?
 Finders:
 Creators:




GeoGebra is Wonderful Because...
 It's a great tool for visualizing and exploring math
concepts
 It's absolutely free
 You don't have to be a computer programmer to use it
 There are many GeoGebra constructions on the
Interneteither use them directly or modify to your liking (just File/Open the web address)
 You can embed directly in webpages, thus students don't
need to install any software
 It understands lots of other math like parametric curves,
conics, derivatives, integrals, taylor polynomials, geometric
transformations, statistics
 It has other powerful features such as a spreadsheet, CAS (computer algebra system), 3D (next version)
 iPad and Android versions are in the works




Thank You!


