“Ignorance and prejudice are the handmaidens of propaganda. Our mission, therefore, is to confront ignorance with knowledge, bigotry with tolerance, and isolation with the outstretched hand of generosity. Racism can, will, and must be defeated.” - Kofi Annan

In the video children are asked if they prefer a black or white skin coloured doll and why. In addition children are asked what colour skin they would prefer to have as well as which children are 'dumb' or 'smart' etc. I won't say any more, you can watch that video here.
Just a quick browse on YouTube and you can find many studies on the same topic. Here is another video for e.g. (also linked to the above study) that shows also how clueless children are regarding WHY they have such prejudices. The question does really come to 'What are we teaching our children?'
Commonly known as the 'blue eye / brown eye experiment' , 'The Eye of The Storm' is ''A wake up call for all ages [that] teaches about prejudices using a dramatic framework [which] provides an examination of the realities of discrimination as experienced by actual students in [her] classroom of [third graders]. Elliott [demonstrates] how quickly children can succumb to discriminatory behaviour. The video chronicles her, now famous, exercise where she divides her class based upon the colour of their eyes and bestows upon one group privileges and on the other group impediments.'' (Source: www.janeelliott.com)
What's interesting is the follow up of the experiment that came 15 years later, 'A Class Divided' that explores what the children ''in Jane Elliott's daring classroom exercise learned about discrimination and how it still affects them today. Ms. Elliott meets with some of her former students to analyse the exercise in pejudice and its impact on their lives'' (Source: www.janeelliott.com).
I strongly recommend everyone to watch the above two documentaries and read about Jane Elliott's experiments.
Prejudice is truly killing us. Enough is enough!