Razor Clams and Ocean Acidification in Oregon

In this lesson, students investigate the effect of carbonic acid on razor clam shell mass in order to connect climate change and ocean acidification with their daily life on the Oregon Coast.

Step 1 - Inquire: Students reflect on their own activity at the beach and learn about how beach recreation, ecosystem services, clamming, and tourism may be disrupted by climate change and ocean acidification.

Step 2 - Investigate: Students measure razor clam shells' mass before and after placing them in water acidified with carbonic acid.

Step 3 - Inspire: Students create a student action project to share their learning with someone outside the classroom.

Positives

• This lesson introduces students to climate change and its effects on marine life. 

• For the lab in the Investigate section, students measure the pH and change the water in the beakers over a five-day period. The monitoring does not take the entire class period, so students and teachers can be engaged with other work or content at this time.

Additional Prerequisites

• Students should be familiar with the concept of pH, the pH scale, and the tools to measure it.

• It may be helpful for the teacher to pre-fill group names in the Student Spreadsheet before sharing it with students, to avoid issues with data loss or overwriting as multiple people edit the document at once. 

• Teachers need the following materials ahead of the lab:

• Shells

• Students can bring their own shells (that they are willing to part with) to use in the lab

• You can use a proxy for shells if you live far from the beach (e.g., chalk sticks)

• Digital scales

• Sharpie pens

• Drinking straws

• Erlenmeyer flasks

• Bromothymol blue solution

• Beakers

• Marking tape

• Access to tap water

• Access to an oven or incubator to dehydrate your shells to measure their dry mass

• Cookie sheet or similar for when the shells are being dried

Differentiation

• Students choose their summative student action project using the choice board in the Inspire section.

• Students can set up further comparisons or controls with clam shells in a bath of vinegar, tap water, or 10% ammonia solution to track changes given different starting pH levels.

• Teacher can show this 16-minute video if time permits: Climate Change: What Is Ocean Acidification?

• To go further into the chemistry of the effects of carbonic acid on shells made of calcium carbonate, please see the following links from Woods Hole Oceanographic Institute and the Environmental Protection Agency:

  • Woods Hole Oceanographic Institute
  • The EPA's Understanding the Science of Ocean and Coastal Acidification

• If you and your students are not from the Pacific Northwest, consider researching the Indigenous people, foods, and resources where you live.

• This lesson presents a climate change problem. Consider following it with a lesson on a climate change solution, such as trees sequestering carbon.

This lesson investigates Oregon's marine resources and ecosystem services. It describes the razor clam, a significant marine species, how it is harvested, its economic advantages, and how ocean acidification brought on by climate change has affected it, other shellfish, and marine resources. This interesting lesson will enable students to develop strategies for coastal communities to protect their marine resources and biodiversity. After all the materials were fact-checked, the lesson passed our science review.

Note On Standards:

This lesson is aligned to Oregon standards. Review the aligned standards directly in the lesson plan document and teacher slideshow.