http://www.bbc.co.uk/schools/gcsebitesize/art/video/photography/
The BBC has put together an online basic revision topics for teens – called BiteSize – and under art it has a group of brief videos on Photography.
About one and a half minutes each. they cover:
camera types, focus, aperture, exposure, shutter speed, depth of field – all in a very simple visual way. No hideous opaque jargon. Very accessible. But prepares you to make creative choices.