Basically you get either a higher test or a foundation test, higher papers give you the chance to get grades 1-9 whereas foundation gives you the chance to get a 1-5. The foundation tests are easier which is normally for the people who struggle with the topic and higher is for like high academic...
A 9 is an A** and then it goes down so an 8 would be an A* and then so on all the way down. A 3 would be a pass and below isn't a pass so basically a U or F something like that