If you are studying IG physics and you are in Year 9 or above, here is the page where you can download the Cambridge 2012, 2013 or 2014 syllabus – or everything you need to know. Download the file for your entry year and look for the Contents part, containing Core and Extended. Core is for grades U to C, extended from D to A*. Remember, they’ll ask you questions in different contexts, same stuff, just dressed up differently.
This is a very useful site. All the past papers you need, plus markschemes
If you are studying MYP – watch this space for details of your own course content