90 Minutes  |  4th – 8th Grades


In the water filters activity, students will be introduced to the sources of pollution and the consequences of water pollution through the Who Polluted the Charles River activity.  They will then break into small groups and design a water filter using a two liter bottle and a variety of materials which can be ‘purchased’ using their allotted budgets to filter out a sample of “polluted water.” The materials available range from coffee filters to sand, and it enables students to be creative with the methodology of water filtration.

As students work on brainstorming ideas, they will be asked questions on their ideas for their water filter. Will the filter work quickly? Did you use a lot of material in your filter? Is your filter “expensive”?  Such questions will enable students to consider the factors that affect their water filter and ultimately influence their final design. Idealistically, the students will design the best possible water filter based on informed decision making from following the design process.

This gives students a perspective on the challenges of turning polluted water into potable water and the realistic limitations when designing a desired product.  The activity ends with a discussion about water shortage issues, and water reuse initiatives that will be more and more prevalent in water-scarce areas around the nation and world.

Lesson Plan:
Lesson Plan – Water Filtration

Water Filtration Handout
Water Filtration Handout – Elementary Version

Who Polluted the Charles? + Oil Spill Activity + Water Filtration Prezi