Here is a list of constructive activities that anyone (no matter what age!) could find worthwhile on a rainy day!

Web-based

Need Installation of Free Software

Phun  - gamelike physics sandbox

Download from http://www.phunland.com/wiki/Download

Tutorials at http://www.phunland.com/wiki/Tutorials 

Google Sketch Up – create 3D designs and structures. 

Download from http://sketchup.google.com/

Tutorials at http://sketchup.google.com/training/videos.html

Westpoint Bridge Designer - design and test bridges

Download from http://bridgecontest.usma.edu/download.htm

Tutorial at http://bridgecontest.usma.edu/tutorial.htm

Pivot - make stick figure animations

Download from http://www.geocities.com/peter_bone_uk/pivot.html

Tutorial at http://www.instructables.com/id/Simple-FREE-Flash-Animation-Pivot-Animation

Submit a suggestion

If you know of other websites or free software that enables users to engage in constructive or creative activities, please email your suggestions to mmeijers at ictmindtools.net