Water critters is a one-day session designed to measure stream and water quality through the collection and identification of indicator macroinvertebrates. Participants will investigate the quality of the stream environment through the use of the biotic index. The biotic index is a scale that indicates the type and abundance of organisms in a representative sample of the environment to assess the quality of freshwater ecosystems. This live, one-day session is designed for high school teachers and is aligned with the Arkansas K-12 Science Standards in Environmental Science.