She set up housekeeping with her mother. She took a job in New York, as a librarian and enrolled her daughter in a nearby public school.# Dorothea and her mother took the ferry everyday into a neighborhood packed with poor people, newly arrived in America. Suddenly Dorothea was exposed to likes of Hester Street, the most densely inhabited few blocks in America, crowded with scenes and endless visual excitement. She became less interested in school and more interested in the city's ethnic and cultural life. #She started ditching and took to roaming through galleries and museums. She absorbed the sights, sounds and smells of lower-class life in turn-of-the-century New York . And in doing so acquired by instinct the craft of being the observer unobserved. And before she was full-grown she had established the distinct elements of her later working style, an eye that looked hard and remembered. #After graduating despite what amounted to an aversion from classroom, for any formal learning situation, Dorothea enrolled in the New York Training School for Teachers on 119th street. Her attendance was a concession to conformity, to her mother's and grandmother's desire for respectability. She was already certain that her life would be spent with a camera. "My mind made itself up," she later recalled, and could add no more other explanation for the decision than: "It came to me that photography would be a good thing for me to do." #She was not yet twenty, and she had never owned a camera. .
Lange might have shunned the classroom but when she wanted to learn something she was tenacious, aggressive, and persuasive. She talked her way into a series of apprentices, perhaps the most important with Arnold Genthe. Among her other teachers were a succession of "loveable old hacks", including one wandering tramp who knocked on families doors showing his wares and offering to take the families picture. Only once did she take an academic class at Colombia University.