My GCSE Maths Notes cover the subject content of a UK syllabus I've taught a number of times. The notes are self-contained i.e. they do not assume prior knowledge of the subject (they are not just brief revision notes). They are somewhat longer than the notes I've provided students with in class, but (deliberately) not as long as typical textbooks. They are about 200 sides of A4 if printed out in the webpage format that I wrote them. The notes are intended to be of use to both students and teachers. Note - Ages of UK GCSE students are typically equivalent to 9th/10th grade in USA.