Frederick Douglass chose to celebrate his birthday on February 14th, though he did not know for sure what day he was born (see The Mystery Behind Frederick Douglass’s Birthday).
Here are related resources:
Frederick Douglass from Slavery to Freedom: The Journey to New York City is from Google Arts and Culture.
Text to Text | Colin Kaepernick’s National Anthem Protest and Frederick Douglass’s ‘What to the Slave is the 4th of July?’ is from The New York Times Learning Network.
Memo to the White House on the Contributions of Frederick Douglass is from The Atlantic.
Frederick Douglass also gave a famous speech on a July 4th, titled “What Is The Slave To The 4th of July?” Here’s a video re-enactment:
These seem to be some decent lesson plans:
From Courage to Freedom: Frederick Douglass’s 1845 Autobiography is from EdSitement.
Narrative of the Life of Frederick Douglass Unit is from The Utah Education Network.
Frederick Douglass Fights for Freedom is from The Zinn Education Network.