Here are some links to past papers and mark schemes for some of the more common exam boards:
Edexcel Maths IGCSE old spec (4MA0)
Edexcel Maths A level old spec (9371)
Here is a selection of YouTube clips for your interest and amusement:
Zeno's paradox of Achilles and the tortoise
The famous Monty Hall problem - could you win the car?
Richard Feynman on knowing something