Most of the stories about resistance to slavery that I am aware of are about people who escaped slavery or who were free for some other reason. While not being de jure or de facto human beings and being the constant subject of brutal torture would make it extremely difficult to organize, I am curious if there was any effort to do so by people who were unable to escape.
Although we often think about resistance as being about uprisings, revolutions, or escaping, there are other ways to frame how enslaved people organized to gain control of their lives, bodies, and minds. This response by /u/sowser explores family bonds among enslaved people and speaks to part of that.
We can also look at laws and statutes passed in states where slavery was legal to get a sense of another way enslaved people organized: education. Slave owners saw an explicit connection between literacy and insurgency, and as such, worked to keep enslaved people illiterate. To quote Heather Andrea Williams, the author of Self-Taught: African American Education in Slavery and Freedom, "Literacy among slaves would expose slavery, and masters knew it." The Mississippi code of 1823 provides the most explicit, and common, approach to the matter.
All meetings are assemblies of Slaves, or free negroes, or mulattos, mixing and associating with such slaves, above the number of five, at any place a public resort, or at any meeting house or houses, in the night, or any school or schools, for teaching them reading or writing, either in the day or night, under whatsoever pretext, shall be deemed it considered an unlawful assembly, and any Justice of the Peace [is authorized to] enter the house or houses where such lawful assemblage or meetings may be, for the purpose of apprehending and dispersing such slaves, free negroes, or mulattos, and to inflict corporal punishment on the offender or offenders, at the discretion of any such Justice of the Peace, not exceeding 39 lashes in the manner hereinafter directed.
Laws like Mississippi's allowed slave owners and local law enforcement to investigate slaves at any time, for any reason for suspected literacy-related activities. The phrase "under whatsoever pretext" extended those permissions to time when enslaved people were working. There are stories about an enslaved person with basic literacy skills teaching children to read while they were - to all outwards appearances - teaching children to sew. These laws like these made it essential for enslaved people to be thoughtful and careful about literacy. Being strategic required organization.
These networks were informal and often based on relationships. There are multiple accounts of enslaved people picking up basic literacy as a result of eavesdropping or being in the room while owners' children were being tutored. In one such account, a woman's owner and his wife spelled out words they didn't want her to hear. She would memorized the spellings and relate them to her uncle, who was literate. She developed an understanding of the alphabet and words, even without explicit literacy instruction, and eventually wrote a memoir.
Enslaved people created a network of covert schools that met in the middle of the night or just before dawn. In some cases, they would meet on riverboats, anchored in the middle of rivers that bordered states with differing laws around literacy. Networks enabled abolitionists from the north to connect with enslaved people who could read in order to teach them how to teach others to read. Enslaved people weren't typically allowed to have pens and writing paper but abolitionists would work to get supplies to enslaved women, especially those who worked in homes with young children. There are multiple first hand accounts of young enslaved women lingering in the room when parents read aloud to their child and would copy down the letters and words they heard the parent read when it was safe to do so.
Up until the passage of the 13th amendment, there was a constant back and forth between literacy efforts among enslaved people and various state laws and statues. North Carolina passed a law that established any white person caught with literacy materials (defined as writing implements) and suspected of teaching reading, writing, or math would be fined $200. A free Black person might be fined, impressioned, or publicly whipped. Any enslaved person could receive up to 39 lashes. A similar law passed just 20 years previously made no mention of enslaved people teaching others. In effect, we can infer that each time the state or a community passed a stricter or harsher ruler related to literacy, it was because the organization among enslaved people was working.