Duration: 45 minutes
SPIRIT Skills:
- Critical Thinking
- Curiosity, sense of wonder and openness
- Problem-Solving
- Resilience
- Creativity
Brief Description:
Each group tests their self-built water filter by pouring “polluted water” (a mix of clean water with natural impurities such as soil, small leaves, sand, or food colouring) into the top of their bottle filter. The water flows through the layers of materials and drips into a clear container placed below. Students observe what happens, collect the filtered water, and compare the before and after. They record their observations by drawing the two water samples and describing them using adjectives (e.g., cloudy, clearer, brown, almost clean). Groups compare their results with one another and discuss why some filters worked better than others. The goal is not just to get clean water, but to understand the filtering process and how different materials influence the result.
How does this develop particular SPIRIT skills
- Curiosity, sense of wonder and openness: Students are motivated to explore how each layer affects the water and to ask questions about what they observe.
- Critical thinking: Learners reflect on the effectiveness of their filter designs and consider ways to improve them.
- Problem-solving: They experiment with different combinations of materials and adjust their approach to achieve better results.
- Resilience: Students persist when initial attempts do not produce clean water, revising their filters and testing again.
- Creativity: They try innovative ways to arrange or combine materials to optimize filtration outcomes.
What do we want to achieve regarding SPIRIT skill development (student understanding and/or behaviour)?
- Curiosity: Students explore how different materials affect water clarity and ask questions about the process.
- Critical thinking and Problem-solving: They compare outcomes, reflect on cause-and-effect relationships, and adjust their approach to improve results.
- Resilience: Learners gain confidence in making predictions and learn to persist when initial attempts do not produce the desired results.
- Creativity: They develop imaginative ways to combine materials for better filtration results.
- Connectedness: Through collaborative reflection, students consider how their solutions relate to real-world water challenges and the needs of others.
Academic/Curriculum Objective connection
- Science: filtering, observation, comparison, and drawing conclusions
- Technology and Engineering: evaluating the performance of a functional design
- Mathematics: comparing quantities (volume of filtered water), simple measurements
- Language development: describing observations and presenting results
- Environmental awareness: understanding how filtering simulates real-life water purification
Materials and tools needed for implementation
- Each group’s homemade filter
- Pre-mixed “polluted water” in transparent containers
- Clear cups or jars for collecting filtered water
- Drawing sheets or observation charts
- Markers, pencils for labelling and sketching
- Towels, trays or plastic sheets to manage spills
- Optional: magnifying glass for closer observation
Preparation notes
- Prepare polluted water in advance using safe, natural materials (e.g., soil, coffee grounds, tea leaves, food colouring)
- Label each group’s container to track results
- Create a simple observation chart or two-frame drawing sheet: “Before / After”
- Emphasize safety and cleanliness: handwashing before/after, no touching dirty water
- Encourage students to speak respectfully about different results (no “better/worse” filters — only different strategies)
Guided Questions
- What does your filtered water look like compared to the original?
- Which material do you think helped the most? Why?
- Did the water smell different after filtering?
- Was your filter better at catching big pieces or tiny particles?
- What surprised you about what came out?
- Would your filter be safe enough to drink from? Why or why not?
Stage Debriefing Questions (Optional)
- How close was the result to your expectations?
- Did your plan work the way you thought it would?
- What would you change next time?
- Was your filter more about blocking dirt, or slowing the water down?
- Do you think real water filters work the same way?
Tips and Tricks for dealing with stage challenges
- If a group’s filter doesn’t work at all: normalize it! Say, “Great! You learned something important, now you get to try again.”
- For impatient students: use timers or challenge cards (“Can you test twice in 5 minutes?”)
- For messy situations: assign a “clean-up chief” per group to manage water and materials
- To encourage careful observation: have students compare their water to a clean sample under light
- If time is short: skip re-testing and focus on describing the first result thoroughly