Unplugged project - bottle

This weeks Unplugged Project theme is bottle. Somewhat lacking in inspiration, I looked at my various 'things to do' books and found a page with the title 'Expanding and Contracting' in The Usbourne Big Book of Experiments which descibed three experiments involving bottles. I thought that they looked fun and visually appealing to three young children. So I checked I had all the materials that we needed and this morning we got started. However it wasn't to be a successful morning!

Bottle Fountain:

I made a hole in the screw top of a glass bottle, pushed a drinking straw through the hole and sealed it with playdough. I half filled the bottle with water and food colouring, and replaced the lid with sthe straw. Then we put the bottle in a bowl of hot water and waited...

and waited! The water did rise up the straw but not with enough force to give the fountain effect.

Cooling and shrinking:

Whilst waiting for the bottle fountain not to do its thing, I asked Sarah to break up some ice cubes in a plastic bag using a rolling pin.

We then put the broken up ice into a small plastic bottle and replaced its cap and waited...

and waited! Nothing happened. After a while Sarah said, 'the experiment's working, the ice is melting and turning into water.' However, this was not the result I was hoping for. The ice was supposed to cool the air inside the bottle causing the air inside to contract and pull the sides of th eplastic bottle in.

Magic balloon bottle:

Feeling a little disheartened we started our final experiment. I warmed another glass bottle and stretched a balloon over its neck and then stood the bottle in a bowl of cold water. Then we waited...

and waited! The balloon was pulled down into the bottle a bit but not completely.

So not the most successful activity! We will try these experiments again when the mood takes us though.

Next weeks theme is happy.