Examples of Class Web Sites
http://www.mtholyoke.edu/courses/dvanhand/   (German)
http://www.mtholyoke.edu/~nvaget/ (French)
http://www.geocities.com/szamora.geo/ (Spanish)
http://www.mtholyoke.edu/courses/inakamur/top.htm (Japanese)
Interactive Web Exercises
Web exercises should be designed to test or check students' contextual use of grammar and vocabulary, cultural concepts, etc.  Students are normally able to submit their answers online.  Many publishing companies are now making such exercises available on the web site designed to accompany specific textbooks. 

An excellent workshop on what it means to make an exercise for the Web "interactive" can be found here --> http://web.uvic.ca/~esg8/interact/wkshp/

A list of selected interactive Web exercises:

http://www2.sp.utexas.edu/fr/student.qry?function=questions
(French grammar exercises from the University of Texas)

http://mld2.ursinus.edu/~jarana/Ejercicios/
(Spanish Language Exercises from Ursinus College)

http://mitglied.tripod.de/daf1/Portal.htm
(Grammatikübungen und Aktivitäten--von Deutsch Online)

http://web.uvic.ca/hrd/japanese/listen/
(Japanese Listening Comprehension Exercises)

There are also free templates available for creating online exercises and quizzes.  For a list of these, click HERE!
Web Activities
Web activities are primarily information-gathering activities.  Many publishing companies have such activities as part of the site for a specific textbook--e.g., Treffpunkt Deutsch, Destinos, Neue Horizonte, French in Action ).  For instance, instructors might have students put together a menu for a German dinner by visiting some German restaurant sites, reading their menus and deciding what to include on the menu they put together.  These activities very often include forms which can be submitted online.  A list of such Web activities follows:

http://ml.hss.cmu.edu/FacPages/amgreen/projects/webex.html
(for German--written by Anne Green, Carnegie Mellon University)

http://www.folwell.umn.edu/ACTFL_IALL/Activities/Japanese.html
(for Japanese--from the University of Minnesota)

http://www.humnet.ucla.edu/humnet/french/web1yr/
(for French--from UCLA)

http://www.cortland.edu/www/flteach/usafa/taller.html
(Taller hispano--from SUNY Cortland)
Discussion Boards and E-mail
Although chat rooms, E-mail and asynchronous discussion boards don't fall under the category of "Web Exercises and Activities," it may be useful to discuss their use in the German classroom here.  I have made extensive use of E-mail and asynchronous discussion boards in my German classes since their use has encouraged students to interact and to collaborate with each other both within and outside of the classroom.  This has occurred among classmates and between my students and students, instructors, or other native informants at different universities/schools in the U.S. and in Germany.

Examples of my use of discussion boards in my classes:

THE CODING: How to Create a Web Site
If you wish to create a web site for a class(es), your best bet is to use one of the many free (or not so free) editors on the market.  Newer editions of Microsoft Word also allow you to save a file in HTML (the coding language of web pages) but you will likely have to reformat and tweak the page.  Here are some links that will be useful to you, including a brief tutorial on HTML coding (for purists):

Tutorial on How to Use Netscape Composer 

Other WSIWYG ("What you see is what you get") editors

"Learn HTML in 20 Minutes" (the basics of HTML coding)