Re: I WANTED TO KNOW WHY DOES BUBBLE GUM STRETCH ?

Bubble gum contains rubber-like natural materials such as chicle from the 
tropical sapodilla tree. These materials along with synthetic materials are 
used to give bubble gum elasticity.  Gums are naturally elastic and obtain 
this elasticity by having a molecular structure that can undergo changes in 
in the amount of coiling within the polymer as force is applied.  A spring 
is often used as a model for trying to explain elasticity.  The long 
polymer strands can be thought of as a spring -- as you apply a force to 
them, the coiled chains expand by straightening out.  The air from your 
mouth provides this force. 

A nice web site to learn more about chewing gum is:
http://comptons.aol.com/encyclopedia/ARTICLES/00958_A.html