Asking Purposeful Questions
  • Strategy: Developing STEM Practices & Mindset
  • Skill: Asking Purposeful Questions
  • Time: 90 Minutes

Water Filter

Practice using the engineering design process to design, build and test a water filter.

In this activity, you will make your own water filter



  • To practice the design process that scientists and engineers do
  • To increase ability to predict, observe, question, design and redesign
  • To better articulate how engineers can help make the world a better place



For the discussion:

  • Handout – Water Filter Design Notes

To make the water filters:

  • 2 liter plastic soda bottles
  • Gravel
  • Sand
  • Sponges
  • Paper coffee filters
  • Paper clips
  • Straws
  • Cotton balls
  • Rubber bands
  • Tape (electrical or duct)
  • Panty hose
  • Clay or putty
  • Cotton batting
  • Cheesecloth, mesh, or some other fabric with large porous holes
  • Scissors