Religion in Hull House...

A caption for a photograph of an arts building described the importance of art education for children:

At Hull-House formal art education for children achieved a high priority, again because of the belief that children's moral and spiritual development depended upon exposure to transcendent ideals, especially in a world so rooted in materialism and so lacking in places of beauty.

Eureka! A religion-analog in Hull House is 'transcendent beauty'. The thing that struck me about the picture I have above (perhaps because I was consciously looking for it) was that the piano in the raised alcove, because of the separate/important position it has, and because of the symmetrical arrangement of things around it, has an "altar-like" aspect.

Another religion-analog (by which I mean a method for spiritual experience, or an understanding of the divine reality) is 'reverence for the past': quoted about a Labor museum, Addams finds it important to build a bridge between the generations of immigrants (individual labor) and their children (factory labor).

If these young people could actually see that the complicated machinery of the factory had been evolved from simple tools, they might at least make a beginning toward that education which [educational reformer] Dr. [John] Dewey defines as "a continuing reconstruction of experience."

She seems to be talking about creating explanatory narratives, an origin story of sorts for the American Immigrant factory laborer, which ennobles both their past and their present, something that would seem to be the task of a budding religion.

A third thing, a page claims that the Madonna and Child was an image prominently displayed in art on the walls of Hull House, (for example, here)
and it seemed to me that that might be because it represented the common religion in its most caring and regarding-human-relationships incarnation, visually.

Hull House, because it seems to be more spacious and "nicer" than the surrounding area, the complex has the character of a building set apart for religious worship, only its aims are really education.