The story is basically this: There is a fish with beautifully colored scales who looks better than all the other shabby fish. To make all the fish "equal", the beautiful fish shares his scales with all the other fish and they all are now equally shabby.
Unfortunately, this story is used to teach young kids that everyone must be equal at the expense of individuality. The shabby fish are taught that it's better to take something nice from somebody instead of working hard to make themselves better looking.
Young people reading this story are being conditioned to believe that it's OK to take property from those who have and give it to those who don't have the work ethic to get their own property.
This is liberalism at it's most sinister, teaching children to look to a bigger and more powerful government to give them what they want, instead of working to improve their lives themselves.
In the real world, there is no true "equality", everyone has their own strengths, weaknesses, talents, backgrounds, environment, hereditary traits, and education. All these factors make everyone different from everyone else, not equal.
America is great because we have a diverse population that rewards people for working hard and taking care of themselves. Conservatives believe the government is a hindrance to progress and that the less government is involved in peoples' lives, the more prosperous they can become.
If you would like to read "The Real Rainbow Fish Story" click here. This is a version that stresses individuality, work ethic, fatherhood, and the danger posed by big government.