The Khan Academy is a not-for-profit organisation with the mission of providing a world-class education to anyone, anywhere.
Whilst drifting around the internet I found the Khan Academy website.
Although it’s in “American” – there are YouTube video clips of an American guy Salman Khan teaching topics in Math(s), Science (Including Physics, Chemistry and Biology) and other subjects.
These are very useful for revision and self-study – particulary for 6th form classes.
Here is an example video – on 2D Projectile Motion – something AS Maths and Physics students often struggle with.
Hope it’s useful!