Writing at home
If you're stuck for ideas on what to write about you could visit http://www.pobble365.com/ everyday where you'll find a picture for inspiration. Don't forget those capital letters and full stops! If your target is to edit your work, maybe you could find a blue pen of power at home!
You might like to keep a diary of what you get up to whilst you're not at school.
The year 1 and 2 common exception words can be found here, how many can you read? How many can you spell?
If you'd like to look at a punctuation and grammar SATs paper, here is one from a previous year.