Human Impacts—Pathways to the Ocean

Summary: Students investigate the ways in which plastics and other persistent debris get into rivers and the ocean.

Concepts to teach: Watershed, downstream, litter

Goals: Students recognize that their use and disposal method of plastic and other waste products can have an impact on aquatic and marine ecosystems both locally and far away.

SS.05.GE.01, SS.05.GE.07

Specific Objectives:

  1. Trace a potential pathway of plastic marine debris from school to the ocean through both a water and land route.
  2. Identify several points along the pathway which can intercept plastic pollutants before they make it to a river or ocean.

Activity Links and Resources:

  • Telling the Story: Fifth graders at Millicoma intermediate School created a PSA YouTube video that tells the story of how a plastic bottle cap gets into the ocean.
  • Plastic Bag – A Mockumentary—This four-minute video tells the tale of a plastic bag’s journey from an inland supermarket to the ocean. Caution: Younger students may take the dramatic positive-sounding narration and music literally instead of seeing it as a spoof.
    • Consider playing the video without sound and having students describe what they see is going on.
    • Stop the video periodically and brainstorm ideas for how to intercept the bag at various stages along the journey.
  • Creative Writing—Students write a realistic fiction story explaining the travels and experiences of a waste product that travels from their school to the ocean.
    • Action: Have the student write a ‘happy ending’ to the story, where an action or intervention stops the pollutant from actually making it to the ocean.


  • Probe: Plastics on the Trail—This probe from Alaska Sea Grant’s Alaska Seas and Watersheds Curriculum elicits students’ ideas about how a plastic bottle on a trail impacts the environment.
  • Probe: Connections to the Ocean—Explores student ideas about connections between Oregon communities and the ocean.
  • Using both a map and written instructions, have students describe a water route from a nearby stream to the ocean.