To successfully obtain a 7-page paper on how black leaders are a factor in social change you could follow this formula.
First, you would want to give a definition of social change. This should include the type of social change that black leaders see as most relevant to their causes. While it is easy to just say equal rights, there are many areas of society to which that can apply.
Next you would need to research black leaders who have been successful in accomplishing such social changes. There are some leaders who obtained the changes they felt were needed through the use of politics. Some leaders were more triumphant using a religious route. Then there were those who were notable for their use of violence.
Finally, you could easily devote a page, or more, for each different leader in each of the different fields of social change.