Logjams are important hydrologic features that shape stream channel morphology and create habitat for organisms. In this lesson, students learn about and measure logjams in a wadeable stream and predict how logjams affect macroinvertebrate communities. This lesson is geared toward undergraduates, and we recommend conducting field activities in groups of 3-5. We also recommend using a wadeable stream that contains both an area with a logjam and, some distance away (10-100m), an area without a logjam for comparison purposes. Necessary equipment includes writing supplies (paper, pencils), tape measure, datasheets, and macroinvertebrate identification (ID) keys with functional feeding group information. Students will begin the lesson by examining the riverscape, identifying channel morphology changes and major habitats in the stream, and discussing how these are influenced by logjams. Students will then examine macroinvertebrate ID keys and make a prediction about the functional feeding groups they will find in the different habitat zones. After this lesson, students will be able to identify how logjams influence channel morphology and predict how they affect macroinvertebrate habitat.