Information on characteristics and outcomes of proorams existing under Title I of the Elementary and Secondary Education Act is summarized in this factbook. The information is organized to answer questions concerning: (1) program effectiveness; (2) services provided by Title I funds; and (3) participants in Title I projects. The factbook concludes that Title I programs are effective in improving reading and mathematics skills for Title I students, in increasino test score gains of low achievers, in getting extra funds to poor schools, and in providing a model for designing state programs for low achievino and poor students. It is reported that the major services provided by Title I funds include supplementary proqrams for educationally deprived children, remedial readinq and mathematics, special teachers and aides, smaller classes, more instructional hours, varied instructional approaches, special needs of migrant children, and services for handicapped children. The factbook reveals that in 1979-80, participants in Title I programs included approximately 5.2 million students; about 241,827 teachers, professional staff, and support staff; and parents who served in advisory councils and as home tutors, aides, and organizers. Also discussed are policy considerations for the continued improvement of services for educationally disadvantaged children. (Author/MJL)