Lets say I drop you off in the middle of an African game park along with an african game keeper who is black. Neither of you have weapons, we'll see who gets eaten by Lions first. Would that be a fair test of your intelligence? Its easy to score well when you've been schooled in all aspects of the test your entire life.
Given that the origin of all people genetically comes down to a very small gene pool in Africa I don't know how you come to the conclusion that some races are more intelligent than others.
-isms are rife in human society of which racism is just one. The basic nature of people is towards prejudice, or rather perhaps the basic choice is towards doing little about their prejudices. Whilst we cling to any idea of superiority whether they be based on appearance, cultural origin, gender, wealth etc, there will continue to be unrest in the world. Giving up the -isms can't be mandated by government, it has to be a personal choice made by individuals.