As my friend Koen is pointing out, home work quesitons like this require you to do the research, the reading and the first attempt at the work itself before you can really ask any intelligent questions..
suppose i posted a huge schema with a dozen tables for you; how would that help you at all? you wouldn't understand it, because you were not involved in the building of it, and the specific requirements that were involved. you'd spend a million quesitons asking how to bend my idea into your homework requirements, isntead of building a homework, and learning what was involved.
once you have done some of the research, and you have a specific question, we'd be able to help you a lot better.
help us help you! If you post a question, make sure you include a CREATE TABLE... statement and INSERT INTO... statement into that table to give the volunteers here representative data. with your description of the problem, we can provide a tested, verifiable solution to your question! asking the question the right way gets you a tested answer the fastest way possible!