Talk to your colleagues - they will have resources to help you. You might even be able to trade your expertise in art, literacy and RE for support in the areas you find difficult.
It's too late for you take booster courses, which are just what you need - they're for trainee teachers only - but a friendly tutor at your local teacher training institution might let you borrow the materials. They are apparently very helpful.
Find the Teacher Resource Exchange on the internet
(http:tre.ngfl.gov.uk), and explore their lesson plans and resources.
You could also Google for "primary numeracy" and "primary science". The support you need is all around you.
We're happy to answer your problems about any aspect of your NQT year.
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