This kit illustrates the principles of human heredity through the study and manipulation of models representing the common dominant and recessive genes which determine facial traits. Using over 120 self-adhering plastic components, students investigate possible combinations of genetic factors and resulting facial characteristics of those combinations. In the process, students answer such questions as: Why do I have blue eyes when neither of my parents do? How can a trait skip 2 generations? How is sex determined? How does color blindness pass through successive generations? Which trait is dominant: long or short eyelashes? Which trait is dominant: attached or detached earlobes? In addition to the plastic components, the kit comes complete with demonstration board, stand, teacher's guide and reproducible worksheets for 8 different lessons.