I'm currently working on a project in my school and I have to create three websites with Joomla. So this would be an entry page displaying only 2 pictures which link to the next two pages. Then one page for each section of the school as a sublevel domain. Like electronics.school.at and mechatronic.school.at. My problem is now, that I have to implement a news section on the main domain school.at that shows news from electronics.school.at and mechatronic.school.at combined and on every page mentioned above, I also have to implement a news page but this one should only implement their news. So this will be 3 seperate Joomla pages but the first one should combine the news from the next 2. I hope somebody can help me here.
Do it via newsfeeds. You can display the feeds on other Domains/joomlas. Link to the joomla feed of startpage or categories (for example: http://www.domain.de/rss-feed.feed?type=rss) and display the items with joomlas feed rendering module.