WATERS Mini Lesson

Yakima WATERS Mini Lesson
Modeling the Water Cycle
Targets and Assessment
WA Science Standards Addressed:
 Grades 6-8 PS2-E: Students understand the
movement of particles in the three states of
matter - solids, liquids. This was touched on
through the evaporation/condensation
 Grades 6-8 ES2-C: Students describe the water
cycle and give examples of where parts of the
water cycle can be seen.
 Grades 6-8 ES2-B: Students describe the role of
the sun in the water cycle. In the lesson the kids
make the connection between the heat lamp
acting as the sun and subsequent evaporation.
Students are asked to define terms:
condensation, evaporation and precipitation.
They must identify the phases and/or phase
changes of each term.
Lesson Parameters
Content Area: Earth Science
Overview: The lesson covers the basics of the water cycle.
We talk about how water evaporates from water bodies and
the water vapor rises and is condensed in the atmosphere
when the vapor cools and forms clouds. We go over how
the clouds produce precipitation and rains down onto the
earth and the whole process starts again.
Grade Level: 7th grade
Suggested Time: 90 minutes
Special Materials:
 Water Cycle Model
Learning Outcomes:
Knowledge: The students should be able to explain the water cycle process. They will understand what evaporation is and
be able to describe it in terms of what the molecules are doing.
Skill: They should correctly use terms like condensation, evaporation and precipitation.
Science Concept Background:
Water cycle – surface water is heated up by sunlight and molecules are released as water vapor. That water vapor rises into the
atmosphere and cools off. As it cools, it condenses and forms clouds and eventually precipitation. That precipitation comes down
onto the landscape and runs-off into the rivers and oceans, starting the whole process again.
Water Cycle Model
Heat Lamp
Key question: How does the water cycle work?
The kids set up there model by filling the water cycle model tray with water then close the lid over it. They fill the “cloud” with ice
and set it on top of the model and shine a heat lamp on it. The model is enclosed and the kids effectively create their own water
cycle within it. The water evaporates and condenses on the top of the lid under the cloud when they tap it; it “rains” down onto the
landscape below.
When we talked about evaporation, we went into how molecules behave when they are heated and how they change phases.
Teaching Tips:
Make sure all the kids at the station are watching when one of them taps the model for the droplets to rain down because there is
usually only enough condensation to rain down for one good tap.
Author: Holly Eagleston, Yakima WATERS Project, CWU, Fall 2009