For students of human development, the Human Embryology Animations site is a worthy resource. Created by Dr. Valerie O'Loughlin at Indiana University, the goal of this site is to help students "better understand the complex processes that must occur in embryologic development." The animations are divided into five thematic sections, including General Embryology, Development of the Limbs, and Urinary and Reproductive Embryology. Each animation lasts anywhere from 20 seconds to 8 minutes, and they cover heart tube folding, septum development, postnatal circulation, and 30 or so other processes. The site is designed for students and members of the general public with a basic understanding of human biology, and the animations are well-planned and worth a look. Additionally, they could be used for students reviewing materials for a course like AP Biology.