[GrumpyDave]

In your situation where you only want to use OmniFocus for your school assignments and all your tasks take place at home, you can probably just ignore contexts altogether. However, if you decide to start using GTD for everything else in your life you might use one context called "School" and then other contexts as normal for the other stuff.

The inbox is the temporary landing space for anything that hasn't been "processed" yet. Just like a real inbox on a desk. Stuff lands there. You look at it and decide whether it should be 1) thrown away, 2) done right now, or 3) added to your todo system as a task or project. That's called processing. Processing doesn't mean doing.

As such, if you have tasks that you've decided need to be done and you've assigned them to projects (or single action lists) they're no longer in the inbox because they've been processed.

To see your upcoming tasks you need to be looking at one of the perspectives. The two-weeks view you mentioned is similar to the forecast view on the iPad version of OF. It hasn't made its way onto the Mac version yet. In the meantime, go to the Contexts perspective, click the "View" button to show the filters, and then change the grouping filter to Due Date or Start Date. Continue experimenting until you see what you want and then save it as your own custom perspective.