Year 4 ‘received’ a special letter Colgate telling us that they were developing a new toothpaste for children to fight against tooth decay.
They explained that tooth decay is most commonly caused by eating a lot of food and drinks which contain sugar such as fizzy drinks, sweets and fruit juice. When plaque (a sticky film of bacteria on teeth) mixes with sugars in food, acid is formed. If teeth are exposed to a lot of acid our teeth can become damaged.
Colgate then asked us to create an experiment which investigates the impact of acid on teeth so they could ‘use’ our results to develop a new range of children’s toothpastes to protect teeth against acid and decay.
The class thought about how they could use eggs (because their shells have a similar chemical make up as our tooth enamel) and a range of liquids such as vinegar, Coca-Cola and water to see which liquid would cause the most damage to the eggs and how long this would take.
We thought about how to make our investigation a fair test by using eggs of a similar size and colour, the same amount of liquid in each beaker and the amount of time each egg spent in the liquid. We also discussed why we needed to use eggs rather than teeth, as these would be difficult to get and it would be unethical as it would damage a human being.
We also covered one egg in toothpaste and submerged it into some coke to see if toothpaste protected the egg.
Year 4 then wrote up our investigation including their own prediction of the impact acid will have on the enamel of the ‘teeth’ and a labelled diagram of our experiment.
After 3 days we returned to check the results and found that the more acid a liquid contained, the more damaged it caused to the egg shell and we could use that to explain that the more acid a food or drink had, the more damage it would cause to our teeth.
I HAD NO IDEA