One site I would suggest visiting is Nova's "Magnetic Storm" site at PBS  
This is the website companion to a 50-minute Nova epsiode that aired approximately 3-4 years ago.  I think the video is excellent.  The main topic is magnetic reversals and the supporting evidence, but it also includes some information and visuals of how the magnetic field protects Earth.  I don't think, however, that it has much information on declination.
Grant D. Smith
Western Oregon University - Earth Science Instructor
Oregon State University - PhD student in science education
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On Tue, Mar 4, 2008 at 12:13 PM, Tom-Pierre Frappé <[log in to unmask]> wrote:
Hi all,

I am teaching an online course ( university level, 3rd year).  My
students are having a lot of difficulty visualizing the geomagnetic
field, and making sense of how the declination/inclination changes

Does anyone knows of good online visualization for the magnetic field of
the Earth?

3D would be best, and interactive simulations would be ideal, but I
might be wishing for the moon... you can email me your suggestions off
list, I'll compile them and send a summary back to the list-serve.

many thanks for your suggestions!

Tom-Pierre Frappé
EOS-Science Education Initiative / ECAC & EOSC114 Administrator
Dept. Earth and Ocean Sciences
University of British Columbia
6339 Stores Road
Vancouver, B.C.
V6T 1Z4, Canada

fax:  (604)822-6047
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