> 1: Where do I put the main elements like Cities, Institutions etc etc? should I put everything in Catagories?
Yes, category system is the way to go.
> 2: How to build the structure?
> Every city as one or more institutions
> Every institution has a education level and faculties
> Every faculty had studies
> How are they linked together
You can do this by hand (using category system). Or you try using "workspaces" (new and promising feature in Tikiwiki 1.10, but usable in 1.9.x as a Mod, under the name: "AulaWiki" -> see it though links and information in http://edu.tikiwiki.org )
> 3: How to create a userinterface for Institutions so the can administor their information (only news,Calander, and detail information, no structural changes)
Manually. Or if you use Workspaces (AulaWiki), then menus are handled in a more efficient way. However, it's not well documented yet, but if you are coder, you'll understand the potential of use looking at the code, I guess.
As far a the author, Javier Reyes - jreyes - told me recently ago, a menu from the higher level workspace, could include dynamically items from the menus from the lower level and child workspaces...
Good luck, and hope to hear about your progress in such big installation!
(or even helping improve AulaWiki and worksapces!)
> (as a attachement a premature screenshot of studieportal.nl)