Water Cycle Investigation

Overview

Students investigate how the Sun drives the water cycle and explain evaporation, condensation, precipitation, collection, and runoff. They read a short informational science text, interpret a diagram, conduct a water-cycle-in-a-bag investigation, and write an explanatory paragraph.

Learning intentions

Students will be able to:

• Explain that water is limited and is continually cycled through the water cycle.
• Describe how the Sun helps water evaporate and how water moves through evaporation, condensation, precipitation, collection, and runoff.
• Use information from a science text and diagram to explain the water cycle.
• Write an explanation of how water moves through the cycle.

Success criteria

• I can explain that water is limited and continually moves through the water cycle.
• I can label the main parts of the water cycle and use arrows to show how water moves.
• I can record observations from the bag investigation and connect them to the water cycle.
• I can write a clear explanation of how the Sun helps move water through the cycle.

Curriculum links

• Georgia Grade 4 Science S4E3: Obtain, evaluate, and communicate information to demonstrate the water cycle, including that water is limited and continually cycled through evaporation, condensation, precipitation, and collection.

Lesson structure (60 minutes)

1. 0–5 min · Hook and prior knowledge. Display a photograph of rain clouds, a puddle, and sunlight using the opening water-cycle images. Ask, “How can the same water be in a cloud, a puddle, and the ocean?” Students think-pair-share and add one idea to a class notice-and-wonder list.

2. 5–15 min · Read and teach. Distribute the water-cycle reading and recording sheet. Students silently read the short informational text, then reread with a partner and underline evidence about the Sun and each process. Teacher models: heat changes liquid water into water vapor during evaporation; cooling changes vapor into droplets during condensation. Clarify that precipitation includes rain, snow, sleet, and hail.

3. 15–23 min · Diagram interpretation. Use the labeled water-cycle teaching slides to display a water-cycle diagram. Teacher models tracing one drop with arrows. Students label a blank diagram on the worksheet with evaporation, condensation, precipitation, collection, and runoff, then answer: “Where does the Sun’s energy enter the cycle?” Review responses with partners.

4. 23–43 min · Hands-on investigation. Place a small amount of colored water in a sealed plastic bag, draw a simple landscape and cloud on the outside, and tape bags to a sunny window or under a lamp. In groups of four, students use roles of materials manager, recorder, observer, and reporter. They predict what will happen, observe every five minutes, and record evidence on the worksheet. Teacher emphasizes that the bag is a model: warming water evaporates, cooler bag surfaces cause condensation, droplets fall as precipitation, and water collects at the bottom. Students must not open the bags.

5. 43–52 min · Explain and write. Revisit the investigation discussion and writing prompt. Teacher asks, “Which evidence shows evaporation? Which shows condensation?” Students write a 4–6 sentence explanatory paragraph using at least four vocabulary words and explaining the Sun’s role. Encourage the sequence words first, next, then, and finally.

6. 52–57 min · Share and formative check. Students read paragraphs to a partner, who checks for a process, evidence from the investigation, and the Sun’s role. Teacher listens to several pairs and addresses misconceptions, especially that clouds are made of water vapor rather than tiny liquid droplets.

7. 57–60 min · Exit ticket. Students complete the final three questions on the water-cycle exit ticket section independently and hand it in as they leave.

Resources

• the water-cycle slide deck
• the water-cycle reading, diagram, investigation log, and exit ticket
• One clear resealable plastic bag per group
• Water, washable food coloring, measuring spoon, and permanent marker
• Tape and sunny window or desk lamp
• Paper towels and group role cards
• Safety glasses, if available
• Timer
• Vocabulary word bank: evaporation, condensation, precipitation, collection, runoff, water vapor, Sun

Assessment

• During reading and diagram work, check that students locate evidence and correctly label arrows and processes.
• During the investigation, review predictions, observations, and student explanations; ask individuals to connect observations to the model.
• Exit ticket: define condensation, identify the Sun’s role, and explain one bag observation using scientific vocabulary.

Differentiation

• Support: provide a process word bank with picture cues, sentence frames (“Water evaporates when…” and “I observed…”), a partially labeled diagram, and partner reading. Preteach water vapor and runoff with gestures and examples.
• EAL/SEN: pair students strategically, read the text aloud, chunk directions one step at a time, allow oral rehearsal or dictation before writing, and provide enlarged diagrams and high-contrast print.
• Investigation support: assign clear group roles, use a visual five-minute timer, and provide a teacher model before groups begin. Offer frequent checks for understanding.
• Advanced learners: explain how runoff can move water from land to rivers and oceans, compare the bag model with the natural water cycle, or describe why a sealed bag is not a perfect model.

Vocabulary, safety, and misconceptions

• Evaporation: liquid water changes into water vapor. Condensation: water vapor cools and becomes liquid droplets. Precipitation: water falls from clouds. Collection: water gathers in places such as lakes, oceans, and puddles. Runoff: water flows over land into lower areas. The Sun: the main energy source that drives evaporation.
• Safety: use only cool or room-temperature water; do not heat sealed bags; keep bags sealed; wipe spills promptly; do not taste materials; wash hands after the investigation; use care around lamps and electrical cords.
• Misconceptions to address: evaporation does not make water disappear; clouds contain tiny water droplets or ice crystals, not only invisible vapor; precipitation is not always rain; runoff is movement over land, not water soaking directly into the ground.

Answer key

• Diagram sequence: collection → evaporation → condensation → precipitation → collection; runoff moves water across land toward lower collection areas.
• Sun’s role: it provides energy that causes liquid water to evaporate.
• Investigation evidence: water level may decrease slightly as water vapor forms; droplets appear on the cooler inside surface through condensation; droplets fall or gather as precipitation and collection.
• Exit ticket responses should identify cooling as the cause of condensation and use an accurate observation from the bag.