This is a short lab to determine blood type in a whodunit burglary scenario. Teacher must provide additional supplies of the simulated blood. Kits are easily purchased online, such as Innovating Science ABO/Rh Blood Typing Kit, IS3101 (Simulated Blood) from amazon. The lab would serve as a perfect compliment to a mini lesson on blood types. Teacher decides ahead of time which blood type each suspect has. The criminal has O- blood.