This site may have been posted already....
Art Institute of Chicago:
Seurat and the Making of La Grande Jatte
I actually like the studies of the Grande Jatte
better...while the final version is quite impressive
(if you have Shockwave - you can really zoom in on
Enjoy the peak at the exhibit. I read the
copyright/licensing information on the site. They do
allow "Fair Use" - if you need to go beyond what "Fair
Use" allows to show the work to your students, contact
information is on the site.
Since this exhibit is over soon, I won't be linking it