I am giving some classes about pest management for some school garden coordinators in San Francisco. Because of this, I have been researching the legalities of pest management in California schools. Below are some links to information that explains the Healthy Schools Act, including lists of pest management chemicals that can be used in schools without posting, and explanations of how to post use of a chemical that isn't on the list.
Note that the rules were set up mainly for inside and landscape usage, rather than for food gardens. The active ingredients that are exempted from the Healthy Schools Act are all basically food products, so are permitted in food gardens, but there are inert ingredients that aren't, so to find out which these are, see the EPA list of inert chemicals that can be used in "food use sites". (Pesticide labels also indicate whether the product is legal to use in food gardens.)
http://apps.cdpr.ca.gov/schoolipm/ This is the main page of the CDPR School IPM Program. It provides overall info on regulations that apply to schools, and allows you to link to the next two useful pages:
http://apps.cdpr.ca.gov/schoolipm/overview/hsa_faq_color.pdf This document provides FAQs on the Healthy Schools Act.
http://apps.cdpr.ca.gov/schoolipm/school_ipm_law/exempt_products.pdf Here you can read about Pesticides & Inert Ingredients that are exempted from the Healthy Schools Act (The actual lists start on page 3--scroll down) (This document also includes links to the EPA minimal risk pesticide list and to the list of CDPR exempted products)
http://www.epa.gov/opprd001/inerts/section25b_inerts.pdf This is the list of inert ingredients permitted for use on food crops.
www.cdpr.ca.gov To see if a pesticide is registered (legal) in California (Click on: Look up pesticide products.)
www.npic.orst.edu. Use this site to research a pesticide ingredient through the National Pesticide Information Center, sponsored by the EPA, go to Look for Active Ingredient Fact Sheets.There are technical or general Information Sheets, depending on your interest and technical background. There are also sheets on inerts and much other useful information on this site. You can also call them to ask for information in person.
www.ipm.ucdavis.edu Click on Home and Garden Turf and Landscape, then on Pesticide Information, then on "Home & Landscape Active Ingredients Database." Also, within the pest management writeups, there are comparison charts for various pesticides, telling you what parts of the environement they might harm and other health and environmental factors you might consider when choosing among alternatives.
See also my book, Golden Gate Gardening. The chapter on IPM includes much information about choosing and using pesticides. In addition, the book's Appendix IV, pages 390-397, explains pesticides in greater detail, including how to read a label and detailed analyses of common active ingredients you may be thinking of using in your garden, so you can make informed choices among your options.