Practical Action have a range of science projects aimed at children aged from 5-16. The activities link Real World Issues to parts of the science curriculum. The activities are designed to be used by teachers in class, but Practical Action have adapted them with a 'Home Learning Guide' so that they can be carried out at home. You could carry out a whole project over a week or more or just pick bits to do. Hope you find them fun and interesting. I really like the 'Ditch the Dirt' one - its very messy!!