Have a trawl through the resources section of this website. Get a selection of Maths puzzles, poems or grammar/punctuation sheets for English, general knowledge quizzes for History/Geog, reading comprehensions for Languages, wordsearch templates. The list is endless. You can photocopy them at break/lunchtime when you know which subjects you will be covering. I can't tell you how many times these resources have helped me out of a tricky situation! Take a stock of pens, pencils and file paper, also. Good luck!