This Manual is designed to assist the educational authorities in evaluating and projecting the size and dynamics of school-age population, particularly when most appropriate data is incomplete of deficient. The discussion of factors affecting school enrolment leads to the presentation of projection methods illustrated by case studies of developing (Colombia, Philippines, Sudan) and developed (France, New Zealand, United States of America) countries. The Manual is related to Projection Methods for Integrating Population Variables into Development Planning, Module Two.