Designed to assist bilingual teachers in providing a coordinated program of studies for students in the Connecticut Migratory Children's Program and for other students whose native language is Spanish, this science curriculum for third grade is one of a series for pre-school through fifth grade. The overall focus of the guides is on Puerto Rican history and culture, placing the development of skills within the context of the experience and social identity of the child. A sequential approach is utilized. The guide contains seven units, related to those in the other third grade guides: Connecticut, Puerto Rico, Latin America, Europe, Asia, Eskimos, American Indians. Appropriate skills are presented in each unit; for example, the skills in the American Indian unit are: inferring the formation of clouds; identifying the types of clouds and symbols used to represent them; identifying the cause of rain; investigating the regulation of rainfall; making and using a rain gauge. Key vocabulary words are listed with each skill. Activities to motivate students to learn each skill are described. The illustrations provided can be copied for instructional use. Much of the material is given in Spanish and English. (CM)