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Daily Do

Why is the Ocean Filled with Plastic?


Is Lesson Plan

Welcome to NSTA's Daily Do

Teachers and families across the country are facing a new reality of providing opportunities for students to do science through distance and home learning. The Daily Do is one of the ways NSTA is supporting teachers and families with this endeavor. Each weekday, NSTA will share a sensemaking task teachers and families can use to engage their students in authentic, relevant science learning. We encourage families to make time for family science learning (science is a social process!) and are dedicated to helping students and their families find balance between learning science and the day-to-day responsibilities they have to stay healthy and safe.

Interested in learning about other ways NSTA is supporting teachers and families? Visit the NSTA homepage.

What is sensemaking?

Sensemaking is actively trying to figure out how the world works (science) or how to design solutions to problems (engineering). Students do science and engineering through the science and engineering practices. Engaging in these practices necessitates students be part of a learning community to be able to share ideas, evaluate competing ideas, give and receive critique, and reach consensus. Whether this community of learners is made up of classmates or family members, students and adults build and refine science and engineering knowledge together.


World Oceans day was founded in 2008 as a call to take action to protect and restore the ocean and is celebrated every year on June 8. One of the greatest threats to the health of the ocean's many and varied ecosystems is plastic pollution.

In today's task, Why is the ocean filled with plastic?, students and their families engage in science and engineering practices and use the thinking tool of structure and function to figure out why there is so much plastic in the ocean. Students and their families will also consider how reducing, reusing and properly recycling or disposing plastics can help protect the ocean. Whether you live on the coast or are landlocked your actions can make a difference!

Investigating Uses of Plastic


Watch the Science Today: Plastic Pollution video before sharing it with your students. You may choose to just share images from the video with younger students.


You will need at least one of the sets of materials listed. When possible, choose items that are roughly the same size.

  • plastic water bottle and glass drinking glass (preferably clear glass)
  • plastic shopping bag (thin plastic grocery bags are ideal) and cloth shopping bag
  • plastic food container (chip bag, cereal bag, etc.) and glass storage container (OK if it has plastic lid)



Watch the Plastic Pollution with students or share images/segments with them. Say to students, "With so much plastic pollution on land and in the ocean, have you wondered why people use so many different types of plastic?"

Give pairs of students a set of materials (one plastic, the other not plastic). Ask students to create a t-chart and label one side plastic bottle/bag/etc and the other side drinking glass/cloth bag/etc.

Tell students to make and record observations about each object. As you move around the room, ask students, "What are some other properties of this plastic bottle/drinking glass/etc. could you describe? Is it hard or soft? Stiff or bendy? Light or heavy? Smooth or rough?" Other properties include color, physical state (solid, liquid, gas), transparency, material, etc.

Ask students, "Both of your objects serve a similar function. What is the function? (Holding liquids for drinking, carrying groceries, storing food). Let's think about times we might want to use the object made out of plastic and times we might want to use the non-plastic object."

Tell students to make a second t-chart. This time label one side Why we use plastic and the other side Why we use non-plastic. Ask students to think about and record why we would use plastic instead of non-plastic and vice versa. Tell students each time they list a use in either column they should write the property of the object that supports their choice. Students might record:

  • Use plastic water bottles to bring water places with you (not breakable, rough sides makes it easy to hold)
  • Use plastic bags to carry groceries (foldable, light weight)
  • Use cloth bags to carry heavy groceries (tear-resistant)

Bring students back together. Say, "Let's see if we can figure out some of the reasons people use plastic." Ask each pair to share one situation they would use their plastic object and one situation they would use their non-plastic object. Consider creating a class t-chart and look for patterns among plastic and non-plastic uses.

Say to students, "Based on our observations, we use plastics because they are (insert student observations such light weight (portable), easy to carry around, and can be thrown away because less expensive than glass and other materials). But we know plastics are polluting the oceans. Do you think we can come up with ways to reduce, reuse, and properly recycle or dispose of plastic objects to keep them from entering the ocean?"

NSTA Collection of Resources for Today's Daily Do

NSTA has created a Why is the ocean filled with plastic? collection of resources to support teachers and families using this task. If you're an NSTA member, you can add this collection to your library by clicking ADD TO MY LIBRARY located near the top of the page (at right in the blue box).

Check Out Previous Daily Dos from NSTA

The NSTA Daily Do is an open educational resource (OER) and can be used by educators and families providing students distance and home science learning. Access the entire collection of NSTA Daily Dos.

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