Weathering the water cycle: Evaporation
A lesson plan for grades 2–3 Science
Students will demonstrate the concept of evaporation by conducting their own experiments, recording their observations. They will be able to draw conclusions from their results.
Time required for lesson
- styrofoam or plastic plates
- three different colored crayons for each pair of students
- measuring cups
- Windows on Science Laser Disk Program on weather (or similar movie)
- student quizzes on FunBrain
- digital camera to take pictures of the plates
- computer with inspiration software to create a picture of evaporation in the water cycle
- computer with internet
Students will observe the teacher wipe a damp sponge across the chalkboard. Students will observe the wet streak disappear. Teacher will ask the students: where did the water on the board go? Teacher will ask where does the water from wet clothes go?
- Choose a dry sunny day. Divide the class into partners. Give each pair a plate and three different color crayons. Students make a shallow puddle of water on their plate. They choose a crayon to trace a circle around their puddle on the plate. Set the plates in different places around the room.
- Let the plates sit in the sun for about an hour. Students can make predictions about what will happen to the puddles of water. Write these predictions in a journal for each pair of students.
- After about one hour, each pair checks their puddle. They choose another crayon to trace a circle around the puddle if it has changed. Compare the predictions that the students had made. Make more predictions about what will happen during the next hour.
- After another hour, recheck the puddles. With a crayon trace another circle around the puddle. Compare the puddle circles drawn on the plates with other plates around the room. Discuss what happened to the water. Ask if there are differences in how fast the puddles in different parts of the room evaporated and discuss reasons for that.
- Explain to the students that water goes into the air and that we call this process evaporation.
- Leave the plates where they are overnight and check them in the morning. Students make predictions of what the puddle will look like in the morning.
- All predictions and responses should be kept in a journal by each pair of students. The next morning students can write their observations of their puddles in their journals and write conclusions about what happened to the water.
Each student stands up to chalkboard and draws a shape on it with a wet sponge. Students will make predictions about which shape will disappear (evaporate) first. Students will discuss why the certain shapes disappeared before others. Ask: Could it be the size of the shapes? Could it be where the shape was made on the chalkboard? Conclusions are drawn from the answers to these questions. Predictions, observations and conclusions will all be written in their science journal.
Students take a quiz on FunBrain. Students put in their student password and click on a weather quiz. Their score will be emailed to your email address if you register on the website.
Students will be assessed by the predictions, observations and conclusions they write in their journals about the two experiments. At least one prediction, observation and conclusion sentence must be written for each day during the first experiment with the plates and water. The sentences must make sense, be spelled correctly, with correct punctuation and be accurate to receive 100 percent. Five points can be taken off for each mistake or inaccuracy.
These questions must be answered correctly in their journals to receive 100 percent and they count off five points each. “Which locations of the plates with puddles in the room evaporate the fastest and slowest and why did that happen?”
These questions can be answered for 100 percent accuracy about the second experiment:
- Why did certain shapes disappear before the others?
- Could it be the size or shape of figure drawn?
- Could it be where the shape was drawn on the chalkboard?
Neatness and organization of their responses in their journal counts for sixty-five percent of their grade too.
This lesson could be adapted for third and fourth grades also. Students enjoy the experiments and recording their results to share with class.
- North Carolina Essential Standards
- Science (2010)
- 2.P.2 Understand properties of solids and liquids and the changes they undergo. 2.P.2.1 Give examples of matter that change from a solid to a liquid and from a liquid to a solid by heating and cooling. 2.P.2.2 Compare the amount (volume and weight) of water...
- 3.P.2 Understand the structure and properties of matter before and after they undergo a change. 3.P.2.1 Recognize that air is a substance that surrounds us, takes up space and has mass. 3.P.2.2 Compare solids, liquids, and gases based on their basic properties....
- Science (2010)
North Carolina curriculum alignment
- Goal 3: The learner will observe and conduct investigations to build an understanding of changes in properties.
- Objective 3.03: Explain how heat is produced and can move from one material or object to another.