Students will investigate hydroponics, plant growth, and sustainable food production by designing and building their own soil-free food-growing system. Using a simple reservoir, nutrient solution, growing medium, and fast-growing plant, students explore how plants can receive the water and nutrients they need without traditional soil.

Over a 10–14 day investigation, students measure plant height, track water use, observe plant health, and evaluate how effectively their hydroponic system supports growth while conserving water. Through engineering design, quantitative data collection, graphing, analysis questions, and a structured Claim–Evidence–Reasoning (CER) response, students connect plant biology to real-world sustainability and agricultural engineering.

Learning Targets

• Design and build a functional soil-free growing system
• Explain how hydroponic systems provide plants with water, nutrients, and support
• Measure plant growth and water use over time
• Collect and analyze quantitative data
• Create and interpret a line graph showing plant growth over time
• Evaluate the effectiveness and water efficiency of a hydroponic design
• Use evidence to propose improvements to the system

What’s Included

Teacher Guide

Background explanations of hydroponics, plant needs, water efficiency, and sustainable agriculture. Includes safety notes, suggested plant and growing-medium options, implementation guidance, expected results, and common classroom pitfalls with practical fixes.

Student Packet

Driving question, hypothesis prompt, variables chart, engineering design plan, step-by-step system setup instructions, plant-growth and water-use data tables, plant observation prompts, graphing task, analysis questions, and a guided CER response.

Data Collection & Graphing

Students measure plant height and water use at scheduled intervals throughout the investigation. They create a line graph of Plant Height vs Time and analyze patterns in plant growth and system performance.

Analysis & Answer Key

Sample growth and water-use data, expected patterns, detailed analysis-question responses, scientific explanations, common sources of error, and a complete model CER connecting plant growth, hydroponics, and water efficiency.

Rubric

Assesses engineering design, variables and controls, procedure, data collection, plant observations, graphing, scientific understanding, sustainability, CER writing, design improvements, collaboration, and safety.

What Students Will Learn

• What plants need to grow and why soil itself is not required
• How hydroponic systems deliver water and dissolved nutrients directly to plant roots
• How to design and test a soil-free food-growing system
• How to measure plant growth and water use over time
• How to graph and analyze changes in plant growth
• How hydroponics can help conserve water and support sustainable food production
• How to use Claim–Evidence–Reasoning (CER) to evaluate an engineering design

Why Teachers Love It:

• Real-world sustainability connection — students explore how food can be grown with less dependence on traditional farmland
• Hands-on engineering design — students build and evaluate their own functioning hydroponic system
• Builds core lab skills: variables, measurement, data collection, graphing, and analysis
• Combines life science, environmental science, and engineering
• Includes long-term quantitative data collection, not just a one-day build
• Encourages students to evaluate water efficiency and sustainability trade-offs
• Includes structured CER writing and design improvement
• Perfect for plant units, sustainability units, STEM projects, environmental science, or engineering challenges

➡️ You can get this STEM as well as all my other ones in this series inside my STEM Investigations Growing Bundle. As more labs are added, the price will increase. CLICK HERE to have a look

Best For

Life Science (plant growth and plant needs), Environmental Science, sustainability, agriculture, engineering design, data collection, graphing, CER writing, STEM challenges, or project-based learning.

Materials Needed

Plastic bottle, cup, or other container; small net cup or plastic cup with holes; fast-growing seedling such as lettuce or basil; water; hydroponic nutrient solution; growing medium such as rockwool, coco coir, perlite, clay pebbles, or sponge; ruler; graduated cylinder or measuring cup; permanent marker; student packet (included).

Estimated Timing

Day 1: Design → build → setup → initial measurements

Days 3, 5, 7, 10 & 14: Plant-growth and water-use measurements

Allow approximately 10–20 minutes on each data-collection day, with additional time at the end for graphing, analysis questions, CER writing, and design evaluation.

➡️ You can get this activity inside my STEM Investigations Growing Bundle.

I also have the following STEM Labs in My Store:

• Blow Cup Challenge STEM Lab
• Paper Table STEM Lab
• Pendulum STEM Lab
• Parachute STEM Lab
• Catapult STEM Lab
• Paper Airplane - Angle of Attack STEM Lab
• Bottle Flip STEM Lab
• Paper Helicopter STEM Lab
• Yeast Balloon STEM Lab
• Balloon Lift Design STEM Lab
• Candy Combustion Calorimetry STEM Lab
• Marble Ramp: Height vs Average Speed STEM Lab
• Clean Water Filtration STEM Lab
• Beetle Genetics STEM Lab
• Adaptations by Design - Extreme Environments STEM Lab
• Newton's 1st Law of Motion STEM Lab - Penny and Index Card - Inertia Test
• Newton's 2nd Law of Motion STEM Lab - Balloon Rocket
• Newton's 3rd Law of Motion STEM Investigation - Thrust vs Nozzle Size
• Electromagnet - Coil Turns vs Magnetic Strength
• Oobleck: Force vs Flow — Non-Newtonian Fluids
• Homemade Lava Lamp - Density & Gas Production - STEM Investigation
• Passive solar water heater - STEM Investigation
• Hydroponic Food-Growing System - STEM Investigation

NGSS Alignment

MS-LS1-5 — Construct a scientific explanation based on evidence for how environmental factors influence the growth of organisms.

MS-ETS1-1, MS-ETS1-3 — Define the criteria and constraints of a design problem and analyze data from tests to determine similarities and differences among solutions.

Assessment

Use the included rubric to score engineering design, variables and controls, procedure, data collection, graphing, scientific understanding, sustainability connections, CER strength, design improvements, collaboration, and safety.