[8] The school opened in September 1904, and in 1905, the second-floor chapel and convent was converted into two classrooms for the seventh and eighth grades.
In 1910, a second two-story building was built north of the original structure, at 909 North Avers Avenue; this brick and timber-joist structure with a wooden interior was in the "Old English" architectural style, with a basement a half-story above the street, a church on the first floor and 12 classrooms on the first and second floors.
[8] As the Baby Boom post-World War II occurred, the school became overcrowded, with enrollment at around 1,500 in the 1950s; classroom sizes went up to 60.
[13] On December 1, 1958, a fire in the north wing of the school killed 92 students and 3 nuns and injured numerous others.
In 1959–1960, a new Our Lady of the Angels School, designed by the Chicago architectural firm of Barry and Kay, was constructed according to the latest required fire safety standards; safety features included enclosed stairways, automatic sprinkler and alarm systems, and the use of fireproof coatings on doors instead of flammable paint and varnish.
[15] A new address of 3814 West Iowa Street, located on the south side of the building, was used in order to distance the school from the fire.
[16] Classes were to resume on December 9, 1958, with students attending in shifts at Our Lady Help of Christians School.
[17] Catholic schools that took some Our Lady of the Angels students include: Chicago Public Schools (CPS) campuses that took some Our Lady of the Angels students include:[19] In September 1960, the modern three-story building with 34 classrooms plus a kindergarten opened.
In November 1968, a parish social hall or "fun building" was opened to host supervised after-school activities.
[23] By 1971, demographic changes in the population of the city’s west side reduced the number of students, with enrollment falling to 878 and the school beginning to experience serious financial problems.
[23] In subsequent years, Catholic residents began to move to the northwest side of Chicago or to the western suburbs.
By the 40th anniversary of the school fire, Our Lady of the Angels mostly educated Black and Hispanic children from preschool to 8th grade, and had a severely diminished enrollment of 130 students, only about 26 of whom were Catholic.
[27] Due to the steep decline in the number of students, the Archdiocese of Chicago closed Our Lady of the Angels School once the Class of 1999 graduated.
[21] At first the Nuestra America Charter High School opened in the former Our Lady of the Angels building.
The building was subsequently leased to Galapagos Charter School until it also closed in June 2016, citing financial pressures.