Teach your students about the types, causes, effects, and barriers to diffusion with this no-prep AP Human Geography unit 3 lesson. It includes a presentation slideshow, guided notetaker, and a worksheet assignment where students practice identifying and explaining the types of diffusion. Answer keys for the activity and guided notes are also provided. All materials are editable and can be printed or used digitally, either in class or for homework and independent study. [updated 2025] IncludesIn