Long Island Sound is an estuary of national significance and provides important economic, recreational, and aesthetic value to the citizens of Connecticut and New York. Investigations have been conducted regarding living marine resources and nutrient loading. However, Long Island Sound is often overlooked as an educational resource. This guide is intended to provide educational resources for formal and informal educators teaching about Long Island Sound. The guide is divided into five sections. The sections are tabbed for quick reference and student pages are formatted for easy recognition and separation from educator pages. This guide begins with an overview of what an estuary is and how organisms survive. This is followed by a discussion about Long Island Sound habitats and food chains/food webs. The second section is a collection of activities developed to work with a few specific Long Island Sound resources--"Invasive Species of Long Island Sound" poster, "Long Island Sound Worth Fighting For!" video, Environmental Protection Agency Long Island Sound Study (EPA LISS) "Sound Health 2008, The Living Sound" video, and the "Sound Facts" booklet (the means for obtaining the resources are provided on page 16). This is followed by several lesson plans focused on Long Island Sound topics, and a Long Island Sound field site set of lessons developed by Long Island Sound mentor teachers. Finally, a section of Long Island Sound resources is provided and is organized by topic. A list of these topics is provided on page 123.