These are some websites you may find of interest:
Maths is Fun is a great site to explain everything mathematical!
mathszone links you to wide range of other maths sites at different levels of learning, with lots of fun games to try as well.
For those of you who like a bit of a science challenge check out this page ready for upper school.
Here is the home of the British Science Association with links to the CREST awards.
The following are Literacy sites:
AND just for fun have a play with words at wordel