Today we are looking at filtering and how it can be used to clean dirty water. This water filter science project is very simplified but gives kids a great overview of how water purification is carried out to give us lovely clean drinking water.
Do not drink the water in the activity
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Water Filter Science Project
Filtering Water – What you need
Dirty water ( or mud and clean water )
Funnels
Coffee filter/paper towel/muslin
Sand
Stones
An empty bottle or other containers
Filtering Water Experiment
The great thing about this experiment is that you can design it however you like.
We set up coffee filters containing sand, stones and then just plain filters.
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We carefully poured the same amount of water through each filter and observed the results.
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More ideas to try – Water Filter Science Project
Set up an experiment where the conditions are:
1 coffee filter
2 coffee filters
3 coffee filters
Is kitchen roll better than a coffee filter, would just a sieve work?
You could also work in stages, so try a colander, then a sieve and then a paper towel. Each stage should trap smaller and smaller particles.
How do filters work?
A filter is a porous material which a liquid can be passed though to separate the liquid from solids suspended in it.
More Filtering Investigations
Make a toy filter.
Try filtering potions using a sieve and colander.
Can you filter water using sand and stones?
More Science for Kids
I’ve got a fun collection of water science experiments, including a water cycle activity, dissolving experiment, ice investigation and density trick!
Try one of our easy science experiments for kids to do at home! We’ve got egg experiments, ice experiments, paper helicopters, STEM challenges and lots more science fun for kids of all ages!
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Suitable for Key stage 2 Science
Properties and Changes of Materials
Use knowledge of solids, liquids and gases to decide how mixtures might be separated, including through filtering, sieving and evaporating.
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Last Updated on August 6, 2024 by Emma Vanstone
This is such a neat experiment. I bet it would be fun to let the kids think of better ways to filter the water. It will definitely give them a better appreciation for our clean water!
So simple, and yet so fun! A very good way to learn about filters and clean water. We will definitely have to try this one, thanks 🙂
We did that once too and it’s amazing how much gets filtered out and how gross that water still is. I think yours was more easily visble, we have very clay like dirt, so it didn’t quite dissolve right.
Thanks for linking up to Science Sunday!