race is the big issue in the united states

We've just had 'race riots' in the States:
Race riots rock the US after Ferguson...

It's an issue which has vexed the country for years - and here's an extraordinary experiment conducted in an Iowa school just after the assassination of Martin Luther King:
Jay Doubleyou: jane elliott - brown eyes vs blue eyes

And it's there in song:
Jay Doubleyou: racial issues

And in art:
Jay Doubleyou: banksy: the provocative artist of our time
Jay Doubleyou: the disappearing banksys

But of course it's not just in the United States:
Jay Doubleyou: every town and city in britain profited from the slave trade
Jay Doubleyou: what is a 'native speaker' of english? the issue of race...
Jay Doubleyou: “you felt uncomfortable about people speaking foreign languages..."

There are lots of materials on the subject for teachers and students:
Racism - Racial discrimination - ESL Resources
ESL Discussions: Conversation Questions: Speaking Lesson: Racism
Breaking News English ESL Lesson Plan on Miss America
Racism Lesson Plans - LessonCorner
69 FREE ESL Human rights, racism, discrimination worksheets
Korean Job Discussion Forums :: View topic - The 'spark' that will ignite racial tensions in the UK
From the Archives: Brave Vicky’s post on Racism | ESL Library Blog

There are academic studies too:
Confronting Issues of Race and Class in the ESL Classroom

From the BBC:
Mixed race, mixed feelings | BBC World Service
BBC NEWS | In Depth | Race | Is Britain a racist country?
BBC - Higher Bitesize History - Race relations between the wars : Revision, Page2
BBC - GCSE Bitesize: Harper Lee

And here's an interesting documentary:
Racism: A History - Top Documentary Films
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