"Man and the Gulf of Mexico (MGM)" is a marine science curriculum developed to meet the marine science needs of tenth through twelfth grade students in Mississippi and Alabama schools. This MGM unit, which focuses on marine habitats, contains an introduction (with unit objectives and brief introductory comments) followed by five sections, each focusing on a particular marine habitat. Habitats considered include: the salt marsh; the mud flat; the sound; the beach; and barrier islands. All sections include a statement of concept(s) to be learned, objectives, and one or more science activities. Objectives, procedures, and background material are provided for these activities which investigate: diversity in ecosystems; salt marshes; mud flat communities; marine organisms and osmotic tolerance; breathing rate of fish as affected by water tolerance; beach and dune communities; particle distribution on sandy beaches; and six barrier islands off the Mississippi/Alabama gulf coast. In addition, sections on the salt marsh, mud flat, sound, and beach habitats contain one or two vocabulary activities as well as vocabulary lists. (JN)