Mai Lesson

Clean Water Challenge

Science · 30 min · Ages 12-15 · Middle school · Away from the screen

This lesson challenges learners to design and construct a multi-layer water filter using common household materials. They will investigate how different materials can remove impurities from water, connecting scientific principles to real-world applications.

What your child gets out of it

• Design a functional multi-layer water filtration system.
• Explain how different materials contribute to water purification.
• Evaluate the effectiveness of a homemade water filter.

What you need

• Empty Plastic Bottle — A 1-2 liter soda or water bottle works well. Parent may need to help cut it.
• Cloth Scraps — Old T-shirt or towel scraps work perfectly. (or Coffee Filters, Cotton Balls)
• Sand — Play sand or garden sand is ideal.
• Small Pebbles — Gather from outside or use craft store pebbles. (or Small Rocks, Gravel)
• Soil/Dirt — A handful will be enough to make dirty water.
• Water — Tap water is fine.
• Paper — For sketching filter designs. (or Notebook, Scrap Paper)
• Drawing Tool — Any pen, pencil, or crayon for sketching. (or Pencil, Crayon)
• Scissors — Adult supervision needed for cutting the plastic bottle.
• Pitcher — To mix and hold the 'dirty water'. (or Large Bowl, Jug)

How it runs

1. Introduction · 5 min
2. Explore & Plan · 8 min
3. Discussion · 6 min
4. Activity · 9 min
5. Summary · 2 min