Grass Roots: Phytoremediation & Filtration
Students will design and conduct a controlled investigation comparing the effectiveness of different grass types in filtering contaminated or imbalanced soil, analyze pH or qualitative plant health data to identify trends or differences between treatments, and connect plant-based environmental engineering methods to real-world ecological and public health challenges.
Overview
Students investigate whether grasses can reduce soil contamination and restore pH. After videos or images of phytoremediation sites, a think-pair-share, and a KWL chart, groups write a testable question and hypothesis, then grow two or three grass types in a water-only control and in containers treated with vinegar, baking soda solution, or saltwater. They measure soil pH, plant height, and visual health every one to two days and analyze trends using graphs and a claim, evidence, and reasoning response. In the culminating task, students write a Phytoremediation Proposal for a contaminated site and present it as a poster, slides, infographic, or talk. Engagement takes 15-20 minutes and setup 45 minutes on Day 1, with data collection on Days 2-10; explanation takes one to two class periods and the proposal project two to three, at 45-60 minutes each.
Lesson Objectives
- Explain how certain grasses or plants can reduce soil contamination and improve pH.
- Design and conduct a controlled investigation comparing the effectiveness of different grass types in filtering contaminated or imbalanced soil.
- Analyze pH or qualitative plant health data to identify trends or differences between treatments.
- Connect plant-based environmental engineering methods to real-world ecological and public health challenges.
- Evaluate the environmental and ethical implications of using plants as bioremediation tools in contaminated environments.
Standards
NGSS · 3
- HS-ETS1-2Design a solution to a complex real-world problem by breaking it down into smaller, more manageable problems that can be solved through engineering.
- HS-PS1-3Plan and conduct an investigation to gather evidence to compare the structure of substances at the bulk scale to infer the strength of electrical forces between particles. (Relates to pH, salt, and ionic contamination effects on soil.)
- HS-ESS3-4Evaluate or refine a technological solution that reduces human impact on natural systems. (Students assess grass-based remediation as a real-world solution.)
CCSS Math · 5
- HSS-ID.A.1Represent data with plots on the real number line (dot plots, histograms, and box plots).
- HSS-ID.A.2Use statistics appropriate to the shape of the data distribution to compare the center (median, mean) and spread (interquartile range, standard deviation) of two or more different data sets.
- HSN-Q.A.1Use units as a way to understand problems and to guide the solution of multi-step problems; choose and interpret units consistently in formulas; choose and interpret the scale and the origin in graphs and data displays.
- HSN-Q.A.2Define appropriate quantities for the purpose of descriptive modeling.
- HSN-Q.A.3Choose a level of accuracy appropriate to limitations on measurement when reporting quantities.
CCSS ELA · 1
- RST.9-10.7Translate quantitative or technical information expressed in words into visual form (e.g., table, chart) and vice versa. (Used during data analysis and student presentations or summaries.)