3 Lab Investigations on the Water Cycle - Evaporation • Energy Transfer • Salinity & Earth Systems

Students will explore evaporation as a driving force in the water cycle through three connected, hands-on STEM investigations. Across short-term and multi-day labs, students measure evaporation rates, model phase changes in a closed system, and quantitatively analyze how evaporation changes salinity.

Using real data, graphing, and CER-based explanations, students develop a deep, systems-level understanding of how energy and matter move through Earth’s hydrosphere.

This bundle is designed to scaffold learning from observable evaporation, to particle-level explanations, to real-world Earth science applications.

Learning Targets

Across the three labs, students will:

• Plan and carry out controlled investigations with repeated measurements
• Measure changes in water volume and mass caused by evaporation
• Analyze how temperature, airflow, and salinity affect evaporation rate
• Graph and interpret long-term data trends
• Construct CER-based explanations using evidence and scientific reasoning
• Explain evaporation’s role in the water cycle, oceans, and enclosed basins

What’s Included

1) Evaporation Race: Measure Evaporation Rates

Students compare evaporation under control, warm, and wind conditions. Through repeated measurements and graphing, they determine how temperature and airflow affect evaporation rate and connect results to real-world puddles, lakes, and oceans.

2) Mini Water Cycle Lab (Closed System Model)

Students create a sealed mini water cycle to observe evaporation, condensation, and water movement. Using qualitative observations and optional temperature data, students construct a CER explaining how energy transfer drives phase changes in a closed system.

3) Salt & Evaporation: Mass, Volume, and Salinity Changes

Students track freshwater, ocean-like, and high-salinity solutions over multiple days to analyze how evaporation concentrates salt. Data-driven analysis connects lab results to ocean salinity, salt pans, and enclosed basins like the Dead Sea.

Included in Every Lab

• Teacher guides with setup diagrams, pacing tips, safety notes, and background science
• Student packets with clear procedures, data tables, calculations, and analysis questions
• Graphing templates with labeled axes and evidence-based comparison prompts
• CER frameworks or structured explanations aligned to science practices
• Answer keys with expected trends, sample calculations, and model explanations
  

Why Teachers Love This Bundle

• Strong conceptual progression from simple observations to complex systems
• Mix of short-term and multi-day investigations
• Excellent integration of Earth science and physical science
• Builds real lab skills: measurement, controls, graphing, and CER writing
• Minimal prep using affordable, classroom-friendly materials
• Perfect for units, stations, long-term projects, or sub plans
  

Best For

Middle and high school Earth science, physical science, water cycle units, evaporation & phase changes, oceanography, data analysis, and CER writing.

Materials Used Across the Bundle

Shallow dishes, water, measuring tools, balances or rulers, zip bags, table salt, fans or lamps, labels, trays, and student lab sheets (all included). Optional: thermometers, hot plates (teacher supervised).

Estimated Timing

• Evaporation Race: 40–60 minutes + 24–72 hours observation
• Mini Water Cycle Lab: 45 minutes + 24–48 hours observation
• Salt & Evaporation Lab: 60–90 minutes setup + 3–7 days data collection
  

NGSS Alignment

MS-ESS2-4, HS-ESS2-4, HS-ESS2-5, HS-PS1-3, HS-PS1-4
Practices: Planning & Carrying Out Investigations; Analyzing & Interpreting Data; Using Mathematics & Computational Thinking; Developing & Using Models; Constructing Explanations; Argument from Evidence

Assessment

Each lab assess experimental design, data accuracy, calculations, graph interpretation, CER quality, and understanding of Earth system processes.