A notebook &
A frying pan
Tell your friend to hold a book against one of your cheeks and simultaneously hold the frying pan against the other cheek.
You will notice that the frying pan feels colder against your cheek when compared to the book.
How does this work?
The frying pan is made of metal and metals are good conductors of heat. The human body conducts heat to whatever the skin is in direct contact with. Metal (the frying pan in this experiment) absorbs the heat from the cheek and the skin feels cold. On the other hand, paper is not a good conductor of heat, and hence, the heat is retained by the cheek and the book feels normal when in contact.
With the help of this experiment, the teachers can introduce the concept of good conductors and bad conductors to children.