you could try singapore math books. They are not uk curriculum, but I used singapore primary math books with my children who I home educated. I have recently put them into school and they were all ahead with their math. It is a really good system.
Singapore math do have a page of their own you could google for, but I get my books from www.halfmoon.com which is a bookshop online. He is also very helpful and can give you good advice too. I can't remember what the name of the series is post primary, but I know that there is definately follow on books for the same system. They also have books specifically for algebra and calculus etc etc....I really like singapore math. It is very visual and well explained with LOTS of drill.
good luck