Students examine their own blood to better understand the clotting process. Students discover their own clotting times studying coagulation rates and bleeding times. They observe the formation of fibrin threads in clotting, and study the effects of calcium on blood clotting. Individualized worksheets and sterile components make this a highly motivational lab activity. Includes 50 capillary tubes, 50 microscope slides, 50 red mixing spatulas, 50 pre-saturated alcohol pads, absorbent paper, 50 disposable sterile lancets, a bottle of saline-citrate solution, a bottle of calcium carbonate solution, a teacher's guide with SDS, and 50 student worksheets and guides. Required but not included: microscopes. WARNING: Choking Hazard. Small Parts. Not for children under 3 yrs.