A GCSE pass ( Grade C will be grade 4 June 2017 ) is essential and achievable, with work, by virtually everyone. It does take time. The content of GCSE mathematics at all levels is wide and you need to be scoring marks in all areas. It is no good having perfect algebra if you know no geometry. You need to know mathematical terms (eg factors, multiples, mode, mean, median) to be able to interpret questions and score marks. The key is to start work early, identify the weakest areas and work on them - on your own or with guidance. Try practice papers to get familiar with the format, use online resources such as MyMaths and BBC Bitesize to practice skills. Consider using a tutor. Research has shown that for boys particularly, tutoring in Mathematics does improve results (Institute of education (2003) - The results for English tutoring are less convincing!)
There are significant differences for students starting to study Mathematics in September 2015 who will sit the first GCSE (9-1) exams in June 2017. There is more content at both Foundation (1-5) and Higher level (4-9) . 9 is the highest grade - a very good A*. 7 is equivalent to current A grade. There are three, hour and a half exams, the first a non-calculator paper. Questions may be more open-ended. Students will be expected to remember more formulae. OCR have a good guide here: http://www.ocr.org.uk/Images/168454-mathematics-summary-brochure.pdf
Notes for students sitting Mathematics GCSE in June 2016 : Two exams are taken at the end of the two year course, even where the exam boards are still offering modular courses! Both the calculator and the non-calculator papers include 'functional' maths (eg asking questions in contexts like working out the best mobile phone tariff) . All current GCSEs have two tiers- Foundation (G-C grades) and Higher (D to A*). Coursework has been completely phased out .
Information here updated July 2015 - please check carefully with your school/college, the exact Board and specification you are on.
www.mymaths.co.uk Very good resource for GCSE and A-level - Many many schools pay for access for their students - USE IT!!
Revisionworld (formerly Revision Net) Good Diagrams esp Circle Theorems- (coursework out of date)
Interactive Maths - US site - lots of Adverts but good interactive 'Flash' demos
GCSE (A-H) Last Examination June 2016
GCSE (9-1) First Examination June 2017
AQA Mathematics Resources Page AQA Also have linear and modular options - more free resources here.
http://www.aqa.org.uk/subjects/mathematics/gcse/mathematics-8300/assessment-resources Resources for new GCSE (9-1)