One topic which we are only just finishing is hazards in which we study earthquakes, volcanoes, wildfires, and tsunamis. It is by far the most deadly part of the course. For every section we used at least one case study for example when looking at tsunamis we studied the 2004 Indian Ocean tsunami. As it is such a large section with lots of background information I do use different websites to supplement the information, for example, https://www.dkfindout.com/uk/earth/ gives basic information which adds layers to your exam answers. You could also use this website for GCSE revision. Miss Bailey also loves this website: http://www.stopdisastersgame.org/en/playgame.html which is where you can play as a town/village planner to protect them from different hazards, my favourite scenario is the wildfire game. Give it a go.
For extra general information on the course, you should look at the AQA website: http://www.aqa.org.uk/subjects/geography/as-and-a-level/geography-7037 which gives a basic outline of the course.