Of the hundreds of eBooks Enslow has available, there are two biography series that would be a great match for books for both early readers and middle school readers.
Famous African Americans series, written for the elementary reader, Paul Robeson is one title in this series of twelve books. A short biography of him is also included in Amazing African-American Actors, which is part of the African-American Collective Biographies series.
There is also an elementary biography of Martin Luther King, Jr., in the Famous African Americans series, as well as a short biography of him in Inspiring African-American Civil Rights Leaders from the African-American Collective Biographies series.
Titles in both series are available in library and paperback editions, as well as eBook formats. These titles are available from your preferred vendor, your independent bookstore, enslow.com, Amazon, and Barnes and Noble.