1. Third Class Discover Primary Science Project
Investigating Plastic- Design and Make ‘Plastic Decorations’
Environmental Awareness and Care

2. Background Information
We learned that fresh milk is very nourishing and contains essential nutrients.
It contains two essential proteins called casein and whey.
Casein forms the basis of cheese and also certain plastics.
The process we used is similar to what takes place in cheese- making.

3. The Experiment
We discussed the different types of plastic and their properties- hard/ soft, flexibility, uses, strength, etc
We warmed 300ml of milk in the microwave and then put it in a bowl.
We then added 1 tablespoon of vinegar to the warm milk.
We stirred the mixture.

7. We then strained the mixture and the blobs (curds) were kept.
The curds were white and rubbery and the whey was a greenish liquid.
We then moulded the curds and pressed them together.
We dried them on some kitchen paper and shaped them.
When they are fully dried we will paint them.

9. We seperated the mixture.

15. The curds felt soft and rubbery.

17. Our new ‘plastic shapes!

20. Our Predictions
We predicted what would happen when we added the vinegar to the milk. These were our predictions.
It would explode
It would get really smelly
It would go gooey
It would get heavy

21. Maths
We estimated how many cups it would take to fill the 300ml container of milk.
We showed our estimations on the graph below.
20 children estimated how many cups it would take.
None of the estimates were correct. It took six and a half cups to fill the container.