ASDAN is a course which I used to run when I was teaching, although it was a while back when we operated the course. It was done to make more use of the form tutor time that we had, and offered the potential to provide an additional qualification for all students in Year 10 and 11. As a form tutor, I had to administer the scheme, and keep track of what students had completed.
The Geographical Association has now worked with ASDAN to put together a course which would have been much better for me to teach than the one I ended up doing.
It's a Geography Short Course with some interesting activities to complete.
You can download a sample of the pupil course book which gives you a flavour of the resource, which has some great images and ideas.