This is a classic carnival arcade game in which the player has to select specific strings from among a strand of strings.  Each string is attached to a colored weight and the object of the game is to pull-up 2-out-of-3, or 3-out-of-5 of the same colored weibhted objects.  This is harder than it looks!

 

 

 

 

 

 

 

An alternative approach is to hide small prizes or a note with a description of the prize under the bottom of a few of the colored weights and if the players is able to correctly guess which string belongs to that weight and pull it up -- he or she wins the prize!!!