Earth's Changing Surface · Weeks 28-36

Designing Solutions for Pollution

A project based approach to mitigating human impact on air, water, or soil quality.

About This Topic

Pollution is one of the most direct and observable human impacts on Earth systems. This topic addresses MS-ESS3-3, which asks students to apply scientific principles to design a method for monitoring and minimizing human impact on the environment, and MS-ETS1-2, which asks students to evaluate competing design solutions using systematic criteria and constraints. Students investigate pollution sources, pathways, and impacts across air, water, and soil systems, then apply engineering design thinking to develop and evaluate mitigation strategies.

The engineering design process is central to this topic. Students define pollution problems in terms of specific criteria (what a solution must accomplish) and constraints (what limits its cost, scale, or material use). Plastic pollution in waterways, stormwater runoff carrying nutrients and sediment, particulate matter from combustion, and agricultural chemical leaching into groundwater are US-relevant case studies that connect abstract pollution chemistry to real community issues.

Project-based approaches work particularly well here because MS-ETS1-2 calls for evaluation of competing solutions against criteria, a task that is genuinely collaborative. Students who defend and critique each other's designs build both technical reasoning and the communication skills needed to advocate for environmental solutions.

Learning Objectives

• Design a prototype for a device that captures microplastics from a simulated water source, meeting specified size and flow rate criteria.
• Critique three different building insulation materials based on their R-value, cost, and environmental impact, recommending the most suitable option for a cold climate.
• Analyze data from a simulated soil remediation project to determine the effectiveness of a chosen intervention in reducing pollutant concentration.
• Compare the energy efficiency of two common household appliances by calculating their operational costs over a one-year period.
• Explain the primary sources and transport mechanisms of a specific pollutant (e.g., nitrogen runoff) in a local watershed.

Before You Start

Sources and Effects of Pollution

Why: Students need to understand the basic causes and impacts of pollution on air, water, and soil before they can design solutions.

Introduction to the Engineering Design Process

Why: Familiarity with the steps of the engineering design process provides a framework for tackling the design challenges in this topic.

Key Vocabulary

Mitigation	The action of reducing the severity, seriousness, or painfulness of something. In environmental science, it refers to efforts to reduce pollution or its impacts.
Engineering Design Process	A systematic approach to problem-solving that involves defining a problem, brainstorming solutions, prototyping, testing, and refining. It is iterative and cyclical.
Criteria	Specific requirements or standards that a solution must meet to be considered successful. For example, a water filter must remove 99% of particles larger than 10 micrometers.
Constraints	Limitations or restrictions that affect the design of a solution, such as cost, available materials, time, or feasibility. For example, a solution must be implementable with a budget of $50.
Pollutant Pathway	The route or method by which a harmful substance travels from its source to its impact point in the environment. This could be through air currents, water flow, or soil absorption.

Active Learning Ideas

Design Challenge: The Waterway Plastic Interceptor

Groups receive a budget, a set of materials, and a simulated waterway (a container with flowing water and floating debris). They must design, build, and test a device that captures at least 80% of floating plastic without blocking water flow or harming simulated fish. After testing, groups present their data, identify specific failure modes, and propose one design modification supported by their test results.

⏱ 90 min·Small Groups

Generate mission

Inquiry Circle: Stormwater Runoff Analysis

Groups model a small watershed by pouring water with food coloring over a landscape model made of soil, grass patches, and impervious surfaces. They collect runoff in a clear container and measure turbidity. They then modify the landscape by adding vegetation buffer strips or settling features and retest, comparing before-and-after results to evaluate which modification most effectively reduced runoff pollutant load.

⏱ 60 min·Small Groups

Generate mission

Think-Pair-Share: How Do We Know an Intervention Worked?

Present two data sets: air quality measurements before and after an industrial filter installation, and water quality readings upstream and downstream of a constructed wetland. Students individually identify what the data do and do not demonstrate about each intervention's effectiveness, then share their criteria for sufficient evidence with a partner before the class develops a shared standard of evidence.

⏱ 25 min·Pairs

Generate mission

Gallery Walk: Evaluating Real Pollution Solutions

Post case studies of four real environmental interventions: the cleanup of the Cuyahoga River in Ohio, the Los Angeles cap-and-trade program for air pollution, green roof stormwater management in Chicago, and a river plastic interception project. Each station includes data on cost, effectiveness, and trade-offs. Students annotate strengths and limitations against MS-ETS1-2 criteria.

⏱ 35 min·Small Groups

Generate mission

Real-World Connections

Environmental engineers at the Environmental Protection Agency (EPA) develop regulations and conduct research to monitor and control air and water pollution across the United States. They might assess the impact of industrial emissions on local air quality or the effects of agricultural runoff on river ecosystems.

Urban planners and architects in cities like Seattle or Denver use principles of energy efficiency to design new buildings. They select materials, window types, and HVAC systems to minimize energy consumption and reduce the building's carbon footprint.

Non-profit organizations like The Ocean Cleanup deploy large-scale systems to remove plastic waste from rivers before it reaches the ocean, employing engineering solutions to address a global environmental challenge.

Watch Out for These Misconceptions

Common Misconception

Pollution only affects the area immediately around its source.

What to Teach Instead

Pollutants travel through air currents, watersheds, and food chains far from their origin. Mercury emitted from coal plants in the Midwest accumulates in fish in Maine lakes. Nutrient pollution from Midwest agriculture creates a large low-oxygen zone in the Gulf of Mexico. Microplastics from land-based sources are found in deep ocean sediment globally. Tracing specific pollutants through systems using mapped data makes this non-local behavior concrete.

Common Misconception

If pollution levels meet legal standards, the environment is safe.

What to Teach Instead

Legal standards are set through a combination of scientific evidence and economic and political trade-offs, and they often lag behind emerging research. Many currently regulated pollutants were considered safe at higher levels in the past. Standards also address individual substances, while ecosystems experience the combined effect of multiple pollutants simultaneously. Students can engage meaningfully with the distinction between legally compliant and ecologically sufficient.

Assessment Ideas

Peer Assessment

Students present their pollution mitigation designs (e.g., a poster or prototype). Peers use a rubric to evaluate each design based on criteria (e.g., effectiveness, cost) and constraints (e.g., materials used, feasibility). They provide one specific suggestion for improvement.

Quick Check

Provide students with a scenario describing a specific pollution problem (e.g., oil spill in a local bay). Ask them to list two potential criteria for a cleanup solution and two potential constraints for developing that solution.

Exit Ticket

Students write down one human activity that causes air pollution and one engineering design principle that could be used to reduce it. They should also identify one potential constraint for implementing that design.

Frequently Asked Questions

How can we use engineering to capture plastic before it enters the ocean?

River interception is currently the most effective strategy because approximately 80% of ocean plastic arrives via rivers before dispersing. Barriers spanning river channels can funnel floating debris into collection vessels without blocking water flow or fish passage. Key engineering criteria include debris capture rate, flow resistance, flood stability, and maintenance accessibility. The Ocean Cleanup organization publishes performance data on their river interceptor systems.

What design features make a building more energy efficient?

Energy efficiency comes from reducing heat transfer between inside and outside. Key design features include high-R-value insulation in walls and roofs, multiple-pane windows, rigorous air sealing to prevent drafts, high-efficiency HVAC with heat recovery ventilation, and passive design strategies such as building orientation, roof overhangs for summer shading, and thermal mass to moderate temperature swings. Performance is typically measured in energy use per square meter per year.

How do we measure the success of an environmental intervention?

Effective measurement requires establishing a baseline before the intervention, defining specific quantifiable success criteria, and monitoring the same variables afterward. For water quality, this means measuring dissolved oxygen, turbidity, or nutrient concentrations at defined upstream and downstream points over time. For air quality, it means particulate matter or NOx readings at defined monitoring locations. The intervention is successful when measurable improvement exceeds what natural variation would explain.

How does active learning help students design solutions to pollution?

MS-ETS1-2 asks students to evaluate competing design solutions against criteria and constraints, not just describe existing solutions. This requires working with actual trade-offs, which cannot be done passively. Design challenges where students build and test devices, analyze real intervention data, and critique each other's designs develop exactly the comparative evaluation skills the standard targets. Students who have argued for their design against peers' alternatives have performed the intellectual work the standard requires.