Effect

The pom-pom stick is a classic. 

It is a versatile trick that can accommodate your theme by exchanging items for the pom-poms (IE: for Christmas, put Mr. and Mrs. Claus). 

The ideas are limited only to your imagination. 

The effect is that you pull down a pom-pom on one side and one on the other side goes up. Finally the pom-pom stick is pulled apart to show no connection. 

For the climax, pinch the longer string and pull the shorter string so both strings are song, then pull the stick apart in the middle to show no connection.