Grade 6 NST Term 2 Week 8: Processes to Purify Water – Lesson Plan & Teaching Tips

Your Week Ahead

This week your Grade 6 Natural Sciences and Technology class dives into one of the most relevant and real-world topics in the entire IP curriculum: how we clean and purify water. Learners will explore the different processes used to remove dirt, debris and harmful germs from water, from simple methods like sieving and settling all the way through to the chemical treatment used by municipalities.

This topic sits within the Matter and Materials strand and builds on what learners have already covered about materials and their properties. Coming into this week, learners should have a basic understanding that water can contain unwanted substances and that clean water is not something we can take for granted. The topic connects beautifully to everyday life, especially for learners who may have experienced water shortages or have family in rural areas where municipal water is not always available.

By the end of the week, learners should be able to name and describe each purification process, explain why clean water matters for living things, and have a basic understanding of how municipal water treatment works. It is a topic that lends itself well to hands-on investigation, so if you can bring in some props like sand, gravel, filter paper, or a simple funnel, your learners will engage much more deeply with the content.

What Teachers Are Searching For

• Water purification methods for Grade 6 NST: Teachers often look for simple, clear explanations of sieving, filtering, settling, decanting, boiling and chemical treatment that are pitched at the right level for Intermediate Phase learners. This week’s plan covers all six methods with age-appropriate language and activities.
• Grade 6 ATP Natural Sciences Term 2 lesson plans: Many teachers search for ready-to-use lesson plans that are aligned to the CAPS ATP, including those teaching in home languages. If you are working from a Sepedi Grade 6 ATP or another home language ATP, the content and sequence for this topic remain the same across language versions. The purification processes and municipal water content are consistent across all language editions of the ATP.
• Hands-on water filtration activity for Grade 6: A practical demonstration or investigation makes this topic stick. Even a simple activity where learners filter muddy water through layers of sand and gravel into a clear container can bring the concept to life and doubles as an informal assessment opportunity.

This Week’s Lesson Plan

This is a 3-lesson week. Here is a summary of how each lesson is structured.

Day 1: Introduce the importance of clean water for people, plants and animals. Learners discuss what happens when water is dirty and brainstorm where water comes from. Introduce the first purification methods: sieving and settling. Learners observe a demonstration or do a simple activity separating large solids from water using a sieve.

Day 2: Focus on filtering and decanting. Learners carry out or observe a practical investigation using filter paper or a sand-and-gravel filter to remove finer particles from water. Discuss how decanting works as a follow-up step after settling. Learners record observations and begin comparing the different processes.

Day 3: Cover boiling and adding chemicals to kill germs. Discuss why removing visible dirt is not enough and why harmful germs also need to be dealt with. Introduce how municipal water treatment works, both before water reaches our taps and after we use it (wastewater treatment). Learners consolidate the week by completing a summary activity listing and explaining all six purification processes.

Download Your Lesson Plan

Download the full 3-day lesson plan as a Word document. Includes detailed activities, differentiation notes, and assessment guidance.

Download Lesson Plan (Word)