In "Thank You, M'am," Roger wanted to say something more than "thank you." What did he want to say?

Part of what makes Hughes's story so compelling is that he does not exactly tell us what Roger would have said to Mrs. Jones.

It is clear that Mrs. Jones had an impact on Roger.  When she caught him at the start of the story, he tried to run away. However, as the story develops, he is touched by the way she looked out for him.  He is willing to go to the store for...

Part of what makes Hughes's story so compelling is that he does not exactly tell us what Roger would have said to Mrs. Jones.

It is clear that Mrs. Jones had an impact on Roger.  When she caught him at the start of the story, he tried to run away. However, as the story develops, he is touched by the way she looked out for him.  He is willing to go to the store for her and is shocked with her proposition that he could have "simply asked" her for the money.  By the time he leaves, he wants to say more to her.  Hughes writes that as she leads Roger out of her home, "the boy wanted to say something else other than “Thank you, m’am” to Mrs. Luella Bates Washington Jones."  It is not clear what this would be.  

We can surmise that Roger wanted to communicate how thankful he was for someone showing care to him.  He might have also wanted to continue a relationship with the woman, as it was clear that she understood his reality and the challenges that confronted him.  Roger might have even told her that her reaction to him had forever changed the way he viewed his life and the choices he made within it.  Simply put, we do not know what he would have said to her.  However, we do know that he was experiencing some authentic emotions of gratitude and emotional debt towards her.