School Garden Wizard is a wonderful website that provides a step-by-step guide to planning a school garden.
There are so many great tips and tidbits on this site that it is hard to do it justice here. The site has everything from the planning process, to incorporating it into the curriculum, and how to maintain your garden and get the community engaged.
Of particular interest to those who are having a hard time getting "buy in" for the school garden, the website offers a guide to making the case for the garden, how gardening relates to National Science Standards, and a worksheet for drafting a proposal!
This website is a definite must read for teachers interested in starting a school garden!