Subject Specific Resources (Free)
Maths
Khan Academy has a wide range of maths lessons for all levels
Maths is fun has a range of online worksheets for maths subjects, all levels and ages. As the tests are online, students know immediately if they have the right answer.
Worksheet fun has a huge selection of printable maths worksheets
Life Skills
Khan Academy provides free online lessons on Careers, personal growth, personal finances etc.
History
School History History organised by topics for ages 11-18
Teachit resources for KS3,4 and 5
Teaching History (USA schools)
ActiveHistory provides educational, award-winning interactive simulations, decision-making games, self-marking quizzes, high-quality worksheets and detailed lesson plans for the history classroom
We've listed a range of resources for different subjects.
English Language & Literature
Creative Writing: The Write Link provides a range of tools and information for budding writers.
Khan Academy has a range of tools for language learning.
ISL Collective has a range of free worksheets for English Second Language.
Pink Monkey has an enormous range of study guides for English literature.
Sciences
'ChemSpider is a free chemical structure database providing fast text and structure search access to over 67 million structures from hundreds of data sources.'
Khan Academy provides free online lessons for a wide range of topics, including Biology, Chemistry, Physics, Engineering.
Help Teaching has a range of printable worksheets for the Sciences, Maths, and English, from kindergarten to grade 12
Business Studies
Free teaching resources uk has a range of worksheets for business studies, KS3 and KS4 as well as most high school subjects.
Help Teaching has a range of business worksheets that cover business etiquette, data analysis, entrepreneurship etc.