What are those insects and other organisms in the stream? Students use a macroinvertebrate card deck and a dichotomous key to identify 20 different illustrated macroinvertebrates. Students learn more about the types of macroinvertebrates in their local natural water sources using this captivating hands-on activity. A great simulation to use during your stream sampling unit! Includes durable, laminated macroinvertebrate sheets, detailed student background information, and valuable Teacher Notes. Complete for 30 students working in groups of six.