There is almost nothing to say about Dr. King's message or legacy that has not already been said, but on this day, we need to remember how important it is to continue to fight for justice, to fight for the oppressed, to recommit ourselves to the struggle for equality.
Here are some very good educational resources:
The National Civil Rights Museum (Memphis, Tennessee)
The Birmingham Civil Rights Institute (Birmingham, Alabama)
The National Voting Rights Museum and Institute (Selma, Alabama)