This book has been written to fill the knowledge gap that exists among school teachers, parents, clinicians, allied Health professionals and the National Health policy makers worldwide, both in the industrialized and developing countries. It concerns the adverse influence that intestinal parasites exert on human Cognition and Educational Achievements among school-age children, especially those attending schools located in the tropical and sub-tropical regions of the world. It is hoped that this text will provide a clearer insight into the need to support integrated control and preventive programmes against these Intestinal Parasites among school-age children regardless of their religious creed, social status, intellectual backgrounds and nationality. Indeed, the most vulnerable population groups at highest risk to the ravages of these intestinal parasitic infections consists of school-age children, pregnant women, the debilitated and malnourished persons and the poor, elderly citizens in many countries around the world, especially those living within the tropics.