We have continued to work on our installation for the Elderflower Fields Festival. We turned empty 2 litre bottles into water lilies, cutting petal shapes into the top of the bottle before using curling tongs to curl the edges. After this we painted our lilies with a mixture of Brusho and PVA glue. Amanda thought the flowers would look really cool if they had solar powered tea lights as the stamen, meaning they would glow at night. We liked this idea but some of us thought the tea lights wouldn’t be waterproof, so we thought about what else might be used. Working in small groups we researched ‘glow in the dark lights’. We discovered you can buy outdoor glow in the dark pebbles from eBay. We decided these might work so Amanda ordered some! We hope they’ll work but will they be too heavy!?

Some of the younger children decided to answer this question. They found pebbles from the playground and placed them on the CD lilies (which were floating in a bowl of water to simulate floating on the pond) to make sure they would still float with pebbles in them. The CDs sunk straight away, which is how we learnt that medium sized pebbles were too heavy!

With this in mind we set out to investigate how much weight the CD lilies would hold before starting to sink. Using 10g weights we first estimated how much weight a single CD might hold before estimating how much weight a larger lily pad (made up of 3-7 CDs) might hold. Working in smaller groups we then tested our hypothesis. We discovered that a single CD can hold approximately 40g before starting to sink. For larger lily pads, if the weight is spread out across the surface it can hold more than if all the weight is placed in the centre.

Amanda