Applets are small, single-purpose computer programs, usually available on the Web through a browser. For this site, I built the applets in GeoGebra, with the goal of making various mathematical ideas more visual and more interactive. However you cannot expect them to teach the concepts they illustrate! They are most effective if they are part of a multidimensional pedagogy that gets students to engage intellectually rather than watch passively.
You can use the applets online, and/or download the corresponding GeoGebra files and modify them to better fit your needs.
Each link below is to a single applet, or to a launch page with links to several applets, or to an article where applets provide the illustrations.
Algebra
Changing a, b, c in `y=ax^2+bx+c`
Complex Number Arithmetic games
Constant Sums, Constant Products
Factored Form of a quadratic
Off and On, understanding linear inequalities
Stairs, slope puzzles
Trinomial multiple representations
Arithmetic
Signed Numbers games
- Fractions
- Pie Slices
- The Well-Chosen Rectangle
Functions
Doctor Dimension, exploring rate of change
Function Diagrams, a parallel axes representation
- Iterating Linear Functions:
- with a table
- with linked function diagrams
- with a 'cobweb' graph
Iterating `f(x)=rx(1-x)` in two representations
Geometry
Only four kindsSSASum of the Angles in a Triangle
Tri, Tri Again (inscribed circle iteration)
Virtual Manipulatives
Other
Pent, a two-person strategy game
Penumbra, some of the geometry of eclipses
Spirograph, exploring symmetric figures created by a circle in a circle
As I create more applets, I'll try to remember to add links in this directory.