Science · Grade 3

Active learning ideas

Evaporation and Condensation

Active learning helps students grasp evaporation and condensation because these processes happen all around us but are invisible without close observation. Hands-on experiments make abstract changes of state concrete, build observation skills, and correct common misconceptions through direct evidence.

• Ontario Curriculum Expectations
• 2-PS1-4

• 20–45 min
• Pairs → Whole Class
• 4 activities

Activity 01

• Plan-Do-Review
• 20 min · Whole Class

Demonstration: Condensation Jar

Fill a glass jar with hot water and cover it with a cold plate or lid. Students observe droplets forming on the cold surface as vapor condenses. Discuss how this models cloud formation, then wipe and repeat with ice for comparison.

Analyze how evaporation and condensation contribute to the water cycle.

Facilitation Tip

During the Condensation Jar demo, place the ice gently on the lid to avoid cracking the glass and allow students to feel the outside of the jar before adding ice to build curiosity.

What to look for

Give students a card with a picture of a drying puddle. Ask them to write two sentences explaining what is happening to the water and what it is called. Then, ask them to draw a simple picture of condensation forming on a cold glass.

• Remember
• Apply
• Analyze
• Self-Management
• Decision-Making
• Self-Awareness

Activity 02

• Progettazione (Reggio Investigation)
• 45 min · Pairs

Progettazione (Reggio Investigation): Evaporation Race

Place equal amounts of water in shallow dishes under different conditions: sun, shade, fan, salt added. Pairs measure and record water levels every 10 minutes over a lesson. Graph results to compare rates.

Explain why a puddle disappears on a sunny day.

Facilitation Tip

For the Evaporation Race, use identical containers and mark water levels with permanent marker so students can measure changes precisely and discuss why some containers lose water faster.

What to look for

Ask students: 'Imagine you are a water droplet. Describe your journey from a puddle into the air and back down as rain. What scientific processes are you experiencing?' Listen for their use of evaporation and condensation.

• Understand
• Apply
• Analyze
• Self-Awareness
• Social Awareness
• Relationship Skills

Activity 03

• Plan-Do-Review
• 30 min · Small Groups

Model: Mini Water Cycle

Students seal water and soil in a zip-top bag, tape to a sunny window, and draw labels for evaporation and condensation over days. Observe changes and predict what happens next.

Construct a model to demonstrate the process of condensation.

Facilitation Tip

When building the Mini Water Cycle, have students draw arrows on their plastic bags to label evaporation, condensation, and collection before sealing the bag to reinforce directional vocabulary.

What to look for

Hold up a clear plastic bag with a small amount of warm water inside, sealed. Place an ice cube on top of the bag. Ask students to observe and record what they see forming inside the bag and on the underside of the plastic, and to label the process they are witnessing.

• Remember
• Apply
• Analyze
• Self-Management
• Decision-Making
• Self-Awareness

Activity 04

• Plan-Do-Review
• 40 min · Small Groups

Puddle Tracker

Mark puddles or spills in the schoolyard with chalk after rain. Small groups measure size hourly and note weather factors. Compile class data to explain disappearance.

Analyze how evaporation and condensation contribute to the water cycle.

What to look for

Give students a card with a picture of a drying puddle. Ask them to write two sentences explaining what is happening to the water and what it is called. Then, ask them to draw a simple picture of condensation forming on a cold glass.

• Remember
• Apply
• Analyze
• Self-Management
• Decision-Making
• Self-Awareness

A few notes on teaching this unit

Start with everyday examples like wet clothes drying or mirrors fogging after a shower to anchor learning. Avoid explaining these processes too early; instead, let students observe and discuss first, then introduce terms as evidence emerges. Research shows students learn reversibility better when they see the same water change states multiple times in a single activity rather than across separate lessons.

Students will confidently explain that evaporation turns liquid into vapor at any temperature, condensation returns vapor to liquid, and both processes conserve matter. They will use accurate vocabulary and connect observations to the water cycle while revising prior ideas through evidence.

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Watch Out for These Misconceptions

• During the Evaporation Race activity, watch for students assuming water only evaporates when heated to boiling. The correction is to have students compare containers at room temperature, in warm hands, and under a lamp, then measure which loses the most water to show evaporation happens at all temperatures.

  During the Evaporation Race activity, have students measure and compare water levels in identical containers over 24 hours to show evaporation happens at room temperature and increases with gentle heat, directly challenging the idea that boiling is required.

• During the Puddle Tracker activity, watch for students believing water disappears forever when puddles shrink. The correction is to have them track mass using a balance before and after evaporation to see the total mass remains the same, just in a different form.

  During the Puddle Tracker activity, provide digital scales and have students weigh containers of water before leaving them in different locations, then weigh them again after evaporation to demonstrate conservation of mass and address the idea of water vanishing.

• During the Condensation Jar demonstration, watch for students thinking condensation creates new water. The correction is to have them compare the amount of water added to the jar with the amount collected after condensation to show the same water is just changing form.

  During the Condensation Jar demonstration, ask students to measure the initial water volume before sealing the jar and then compare it to the volume of condensation collected on the underside of the lid to reinforce that condensation collects existing vapor rather than creating new water.

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Methods used in this brief

• Plan-Do-Review
• Progettazione (Reggio Investigation)