I'm helping my little brother with a project based on energy and force. I have no trouble helping him with more advanced ideas on different sorts of energy, but have no idea where to start with pointing him in the right direction for a grade 4 project. I was thinking of something like sound (fairly topical for me) and it means I can possibly take the bike in to his school (always good for looking cool ) as a support/prop. Can someone help me out with primary school links to this sort of info???