Debris Detectives Field Trip

Engage

30 Minutes

Remind students how far the rubber bath toys traveled once they fell off the ship. Show one or more of the following videos about debris in the ocean.

Alphabet Soup
Altered Oceans is a five part series. Part four is about plastics in the ocean and is very interesting.

Ask students to share experiences they have had of finding odd or interesting debris on the beach or riverbank that may have originated far away. If feasible, take photos of local debris ahead of time to show and discuss with students, or take a walk to see what you might find to share with the students in the classroom.

Look at a few pieces of debris or photos and try to tell their story with the students. Share with students where each item was found. Then ask some or all of the following questions: Does the item look new or old? Are there any clues of what it might have been used for? Are there any clues to the place or date of origin (packaging labels, etc.)? Are there signs that it has been moved by water as opposed to just being deposited in the location found?

Explain to students that the purpose of the upcoming field trip is to look for evidence of the motion of the ocean, or if you are near a river, the motion of the river.

Explore

30-60 Minutes

When you arrive at the field trip destination, ask students to sketch the location in their science notebooks. Remind them to make it large enough to be able to note where each item of debris is located. Ask them to observe and sketch any nearby large structures or natural obstacles that are in the water. As they find a piece of debris, they will mark on the map where it was found, then describe it and the location in their science notebook. Ask them to be very detailed in their description of the item, noting general size, weight (heavy or light), and type of material each is made from. When describing the location site, remind them to note if the item was high on the beach or shore, low, partially covered, etc. If digital cameras are available, students can take a photo of the object where it was found, then write a description of the location in their science notebook.

Ask students to walk the shoreline or river edge to look for debris and document each item as they pick it up.

Explain

30 Minutes

Research local water movement patterns. For sources, consult tide books, records of water level, weather (wind) records, agencies, scientists, fishermen, boat captains, and elders. Try to find patterns that would tell you if the debris has been moved by water, if it would be moved by water if left there, or if it was originally deposited where you found it.

Elaborate

Develop an experiment to monitor the movement of some “foreign objects” to see if your theories are true. Students can use pieces of painted driftwood to throw out into the water and come back the next day or several days later to see if any of the wood can be located. Similar experiments have actually been carried out by some Alaskan researchers. Dr. Sathy Naidu UAF Professor Emeriti painted grains of sand, placed them on the beach and tried to locate them after storms had carried along the coast. 

Evaluate

Ask the students to use the knowledge they have of tides, currents, etc., to formulate a hypothesis about why the debris was found where it was. Have them record the hypothesis in their science notebooks. Evaluate student hypotheses to see if students have used explanations that include knowledge they have acquired during the unit.