AQA
http://www.aqa.org.uk/subjects/science
http://www.aqa.org.uk/subjects/science/year-10-science-tests
EDEXCEL
https://qualifications.pearson.com/en/qualifications/edexcel-gcses/sciences-2016.html
OCR
http://www.ocr.org.uk/qualifications/by-subject/science/
http://www.aqa.org.uk/subjects/science
http://www.aqa.org.uk/subjects/science/year-10-science-tests
EDEXCEL
https://qualifications.pearson.com/en/qualifications/edexcel-gcses/sciences-2016.html
OCR
http://www.ocr.org.uk/qualifications/by-subject/science/