In The House on Mango Street, what was Esperanza really ashamed of besides the clothes?
I think that is one of the things Esperanza, and anyone else in her situation, is ashamed of. She is afraid of her school friends or her teacher seeing where she lives. She is embarrassed, but also dreams of a house where she can live without leaving in the middle of the night to avoid the rent payment, or where there are no leaks, where it's warm. So she has a house (a series of them, as she details), but what she wants is a home.
Poverty has a way of "keeping you down" whether you fight back hard against it or not. It limits the quality of your education, your nutrition, your opportunities, and it is a difficult life to escape. We get a very clear sense of that throughout the collection of Cisneros stories in this book.