Teacher brought some eggs to school. Two were boiled and one was a raw egg.
We can tell the cooked eggs from the raw egg by looking at the date stamp on the side. If the date stamp is on the egg then the egg hasn't been boiled yet. If the date stamp is gone then either the egg is boiled or else the egg came from the farm rather than the shop!
We can also tell raw eggs from cooked eggs by spinning them.
Cooked eggs spin quickly and they are very well behaved, they stop spinning when they are asked (by putting fingers lightly on them). This is like a child in the car with his seat belt on. If the egg (or car) stops suddenly then so does the inside of the egg (the child) because the inside of the egg is joined to the outside in the same was as a child will be joined to the car if the seat belt is on.
Raw eggs are not so well behaved. They are like children with no seat belts on. If the egg is stopped suddenly the inside will keep on spinning (like a child in a car crash who will be thrown through the window if they have no seat belt on.)
We had fun seeing which eggs were cooked and which were raw!