What's in the Sea?!


With approximately 97% of our planet's water residing in the oceans, and these in turn making up around 71% of the planet’s whole surface and with scientists of the belief that between 50-80% of all life on earth is to be found beneath the ocean's surface, the sea is a pretty big deal. Even though humans cannot naturally drink sea water (the salt would make us more thirsty than anything else) and many of us do not live on the seashore, we still rely on it for many everyday things, such as the majority of all global trade happening over water. It’s about time we learn more about the impact we are having on our sea and oceans, ignorance is no longer a valid excuse for what we are doing to it.

The Great Pacific Garbage Patch is an iconic example of this issue. The patch is a collection of marine debris (any litter that ends up in oceans, seas, and other large bodies of water) in the North Pacific Ocean, approximately 80% of the debris comes from land-based activities in North America and Asia. While many different types of rubbish enter the ocean, plastics make up the majority of marine debris for two reasons; first, plastic’s durability, low cost, and malleability mean that it’s being used in more and more consumer and industrial products. Second, plastic goods do not biodegrade but instead break down into smaller pieces. This kind of pollution causes a serious threat to sea life. Moreover, the sea life ingests the broken down micro plastics that cannot be cleaned up from the ocean; the fish are caught in turn for human consumption and indeed, enter the food chain, and then our bodies. What goes around comes around.

One of the few things that can be said to have a worse impact on the environment than the plastics ending up in our seas, is oil spills. Oil spills have catastrophic effects on birds, dolphins, fish and other marine life and the longer-term effects of the multiple oil spills into the oceans on the ecosystem and the subsequent changes to oxygen levels in the ocean are yet to be quantified.

This exercise invites participants to experience the issues around ocean pollution by carrying out ‘clean up’ activities to gain awareness of the associated difficulties. Participants will also be asked to reflect on their own use of non-disposable day to day items in order to consider where they could make changes.

Activity Type

Group/ Experiential


90 minutes

Learning Outcomes

  • To increase awareness about the major ocean pollutants and the consequences of polluting the oceans.

  • To understand our impact on the ocean on an individual level and consider what can be done differently.


Required Material and Tools:

  • Water

  • Vegetable oil

  • Cotton balls

  • Paper towels

  • Cups

  • Newspaper clipping

  • Food colouring

  • Sieves

  • Sand

  • Grass

  • Pebbles

Step-by-Step Instructions:

  1. Divide the participants into 2 groups. Each group will carry out a different exercise relating to ocean pollution simultaneously so they can see what another group is doing while focusing on their own task.

  2. Start the exercises

    1. ‘Oil spill clean up.

      1. Introduce to the participants to the topic of oil spills, providing examples (research online in advance).

      2. To create the oil spill, fill a large bucket with water (the sea) and then pour in a large cup of vegetable oil (the spill).

      3. Experiment using the various tools (grass, sand, cotton balls, paper towels, sieves, pebbles etc) at your disposal to find the most effective way to get as much oil out of the water as possible. Aim to clean up the water completely. [Note: It is encouraged to do research into filtration systems and have a look at the methods used in the real world]

      4. Put all used materials together and note how much materials have been wasted to clean up one cup of oil.

    2. Marine animals and pollution’.

      1. Fill the bucket ¾ full with warm or hot water, put 3-5 drops of food colouring into the water, if needed help it spread throughout the water. This represents the vast ocean and the apparent tiny amounts of pollution we spill into it.

      2. Place one or two cotton buds into the water, giving them time to soak up as much as possible.

      3. Take the cotton buds out and observe if they changed colour. This is the effect small amounts of pollution can have on the fish and consequently on people who later catch and eat them.

  3. Organise the groups to discuss their findings and reflections.

    1. Invite them to think about the impact that oil spills and plastic litter will have on the ocean and the animals.

    2. Ask the participants to individually list all plastic products they have disposed of in the last two days.

    3. What can be done differently, personally and on the society level, to have less litter in the ocean?


Ask participants to carry out a written reflection based on the following questions.

  • Why is it important to keep our ocean free from pollution?

  • Where could alternatives have been used?

  • Which materials can be used as a replacement of plastic?


Instructions for Submission

Submit your and participants’ written reflections. Upload a photo of group work. Instructions on how to upload photos and how to submit things in Moodle can be found here: Instructions on Submission&Uploading

Instructions for Assessment

Provide feedback to at least one participant that has done this activity. Instructions on providing feedback can be found here: Instructions on Feedback

Related Topics

  • Waste management

  • Pollution

  • Plastic

  • Health

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