I have one more ground school exam to pass and then the theory side of things is all done to qualify for my NPPL (National Private Pilots Licence). I find trawling through the books and study papers a bind and found it much easier to get the exams passed by simply trying my luck at mock exams. Long story short: a great source of mock exam questions is the Microlight Hangar. You pick from any of the ground school topics (Aircraft General, Human Performance, Air Law, Navigation, Meteorology & Radiotelephony) and it gives you mulitple choice questions complete with an excellent marking system at the end so you can see just how badly you did but more importantly where you went wrong. Essential site for anyone training for their NPPL.