The song is called the Hokey Pokey where i learned it. It is generally sung by children to teach them their right from left. In the version that i learned there is nothing about stretching. The children stand in a circle facing each other and sing... "you put your right hand in (and by "in" they mean the circle they are standing in), you take your right hand out. You put your right hand in and you shake it all about. You do the Hokey Pokey (meaning you do a silly dance) and you turn yourself around. And that's what its all about!" Often in English people say "do the ____." And that means "Do the ___ Dance" For example: "Do the Tango" would mean "Do the Tango dance." or "Do the Robot" would be "Dance like a robot" In the case of the Hokey Pokey/Hokey Cokey you just follow the directions that are the lyrics of the song. It's a fun and silly way for kids to learn their right from left. Some people think that the name Hokey Pokey/Hokey Cokey comes from the words Hocus Pocus which means "magic". It is a term magicians use when they do a trick. But if you just say "my daughter is learning the Hokey Pokey dance/song Nobody will think magic, they will think of the silly song and dance. Hope this helps. I have to go and do the Hokey Pokey now!

The song is about learning the difference between left and right parts of the body. Here are the words and music http://kids.niehs.nih.gov/lyrics/hokey.htm

http://en.wikipedia.org/wiki/Hokey_Cokey is the official answer. Simply, its a dance that done for fun. Like the Macarena.