Year 4 Eggcellent Science

We have a thriving science community at Caterham and are looking forward to welcoming the Royal Institution on Monday to show us the exciting ‘Explosive Digestion’ interactive stage show. All children from Reception to Year 6 will get to see the demonstrations and experiments which range all the way from biology through to chemistry and physics. 

A couple of weeks ago, Caterham hosted ‘Super Science Saturday’ and a fantastic array of guest speakers including Professor Caswell Barry and Lucy Ann Unwin, author and illustrator of ‘Inside Your Brain’. It was an interesting talk, especially when we were treated to handling a plastic bag of cold, pink porridge so we would know what a real brain felt like, and when we learned a 10 year old student has more brain cells than their teachers! 

So inspired was James, he bought the book and immediately began reading it. His research led him to wanting to draw and annotate his own poster, which he did free hand on A3 card. A very impressive feat to get all that information in and displayed in such an interesting way. 

Meanwhile, this week, Year 4 concluded their egg-shell investigation into which liquids are most damaging to teeth. We left the eggs in the liquids for a week, and all were left at room temperature to ensure the control variables were kept the same. 

Thanks to the bout of hot weather speeding up the reactions, the results were really pronounced (and in some cases, quite disgusting!). 

Our control egg was left in water and suffered no damage at all to the shell. The milk turned into a horrendous smelling solid clump, and we concluded the egg shell (which was entirely enrobed in said clump) was undamaged. We discussed whether we would standardise the test to do in the fridge next time and hopefully this would stave off this from reoccurring! 

Next up were our ‘slightly damaged’ eggs – only in that the shells remained hard but were stained dark brown. This was our biggest surprise of the experiment as some had predicted cola and Dr Pepper would affect the shells the most. 

Then the damage really began to show. Lemon and lime fizzy drink, and orange and mango pitted the outer layer of the shell, and it had begun to rub off. But when it came to orange and apple juice, the damage was very noticeable. The shells had become thin and fragile from losing the outer layers and were in a very sorry state. 

However, it was the vinegar which gave the most shocking transformation. Here the egg not only lost its entire shell to the dissolving power of the acidic liquid but had become transparent and spongy. Most surprising of all, was it gaining 100ml of volume as the liquid had been absorbed over the egg membrane. We had giant, soft, bouncy, vinegar-y eggs! 

This experiment inspired Molly to take up the challenge at home to test the results. The attention to detail of remembering the volumes and the types of different liquids is incredibly impressive as she didn’t have any of the method written down. Mrs Hills-Matthews is avidly awaiting news on Molly’s results to see if they mirror the ones we found in class. 

All in all, a genuinely fantastic set of hands-on, applied results from James, Molly and the rest of Year 4. A huge well done to you all!