This Geogebra file shows dynamically how the graphs of the sine, cosine and tangent functions change as the parameters in their equations are changed. Thanks to Greg Bland for sharing this very visual activity.

Geogebra is a powerful FREE dynamic geometry program. You can download it from
http://geogebra.org

This is a very cool Geogebra file that shows the vectors involved in projectile motion. Thanks to Greg Bland for sharing this file. Three thumbs up!

You can download the FREE dynamic geometry program Geogebra from
http://geogebra.org

This zip file contains two Geogebra files that dynamically illustrate vector concepts - one that shows the forces on an object on an inclined plane and one that shows the resultant of three forces acting at a point. Thanks to Greg Bland for sharing these. Both are excellent teaching aids - 3 thumbs up!

Geogebra is a fantastic FREE dynamic geometry program that can be downloaded from
http://geogebra.org

A collection of four Geogebra files from Greg Bland that will help students understand conics.

Geogebra is a fantastic FREE dynamic geometry program that can be downloaded from
http://geogebra.org

Bill Newell has kindly shared some Google Sketch-up files on volume and cross-sections that he has created.

Google Sketch-up is a free 3-D drafting and geometry tool that can be downloaded from:
http://sketchup.google.com/

The files have been zipped, so you will need to unzip them before you can your them.

Cubic splines are cubic functions which are used in applications such as automobile design. The basic idea is to fit cubic polynomials between two neighboring data points while ensuring that there are "smooth" first and second derivatives at the data points. The program available from this website as a zip file is a useful tool for investigating cubic splines.
http://www.vias.org/simulations/simusoft_spline.html

Distance, time and velocity are an ideal means to understand the concept of derivation. By reducing the time interval until it becomes zero, the average velocity approaches the instantaneos velocity, which is equal to the first derivative of the distance (with respect to time). This is available as a zip file that can be downloaded.
http://www.vias.org/simulations/simusoft_difftangent.html

Choose a function and see the effect on the Riemann sum when you change the slice width. The file itself can be downloaded and installed on your computer or network.
http://www.vias.org/simulations/simusoft_riemannsum.html

Bill Newell has kindly agreed to share some Autograph files that he has created for teaching calculus. To access the files, you will have to unzip them first.

A wonderful implementation of matchstick puzzles.

The website:
http://www.csfsoftware.co.uk/Matchstick_info.htm

Direct download:
http://www.csfsoftware.co.uk/MatchMania/MatchMania.zip