## Thursday, 23 May 2013

### Science: Is it waterproof?

This is a classic science project, great for teaching about permeable and impermeable materials but also as a start learning about what a fair test is.

It is great for even the smallest of hands and it's a fun way to explore impermeable (waterproof) and permeable (non-waterproof) materials.

Before we started we discussed some of the materials we use as clothes and thought about why we don't have paper clothes, what sort of material our raincoats are and why it is that sort of material.  We talked about how we dress differently in the summer to the winter and why.

We also discussed other materials we use in the house and why we use them for the jobs we do, like kitchen towels to mop up mess, would our raincoat do as well?  Then we began...

Before you begin this experiment you will need:
• A glass jar
• An elastic band
• Paper
• Plastic (we used clingfilm)
• polyamide (we used tights)
• Wool (we used a jumper)
• Cotton (we used a T-Shirt)
• Cardboard
• Tissue
• Kitchen Roll
• A pipette (optional but my girls love to use them)
• Water
STEP ONE

Make a table to record your results.

If you can't read it the side on the left reads: If you think it is waterproof colour it yellow and if you think it's not colour it blue.

This is called making a hypothesis!

The right side says:  Now let's experiment!  This time colour the ones that are waterproof (for definite) yellow and the ones that aren't, blue.  These are your results.

STEP TWO

Before we started experimenting, we used the first page, our hypothesis and coloured it in like so...

STEP THREE

MAKING IT A FAIR TEST
To make it a fair test we decided how many drops of water we were going to put on each material (15 in this case) and tested the same surface area for each material by tying it to the top of a jar like in the photo below.

STEP FOUR

We did each experiment one at a time and Honi led the way in which one we did first.  Each time we tested a material we followed these steps:

1. We attached the material for testing to the jar.
2. We used a pipette and counted the drops
3. We waited 5 minutes and observed what happened
4. We coloured in our table to record the results
Of course you don't need to use colours you could just write your results.  Honi wasn't in the mood for writing, hence the colours.  I did ask her at the end which material would work best to make a raincoat.  Maybe when you have finished you might ask your little scientist too?

Things we learnt from this experiment:
• permeable means a material that water passes through
• impermeable means a material that is waterproof
• hypothesising
• materials and their properties
• sorting materials
• fair tests

FOR CHILDREN WANTING TO TAKE THIS FURTHER:
Write up a conclusion and how we could use the results from this experiment and put them to use in the 'real world'.

I hope you find this resource useful.  If you like this one you might like to try some of the other experiments on An Ordinary Life's Physics, Biology or Chemistry Pages!