Explore the effect of temperature and raw sewage on water quality, The experiments presented in this kit include poisoning effects of sewage and temperature on aquatic life biological oxygen demand and the changes in BOD interaction of sewage decomposers and other aquatic organisms and the collection and observation of actual water samples, Includes enough materials for 30 students to work individually comprehensive Teacher s Guide and reproducible student worksheet, American Educational Products have a lead ship time of 21 days, SKU: AMED1503