Chemistry
Revision materials can be found at:
http://www.sqa.org.uk/pastpapers/findpastpaper.htm?subject=Chemistry
contains past papers and answers!, as well as links to Course Specifications, data booklet, etc
http://www.bbc.co.uk/bitesize has summary notes and self test material – recommended
Crocodilia for Crocodile Chemistry has a variety of study materials but not quite so good for revision purposes
http://scholar.hw.ac.uk/sco.html for Higher and Advanced Higher … registration and password required