|The Horace Mann Historic District qualifies for placement on the National Register of Historic Places under Criterion A, for its community planning and development, fitting within the guidelines put forward in the National Register Multiple Property Listing Historic Residential Suburbs in the U.S., 1830-1960. The district is the first Gary Land Company (the land holding subsidiary of the property owner the U .S. Steel Corporation) addition to the city to be platted and laid out with consideration given to the automobile . The district is a significant example of the type of planned expansion of the city executed by the Gary Land Company. The district also qualifies under Criterion C for its architecture. The district has many fine examples of architectural styles popular between the two World Wars. Several of these homes represent the work of locally and nationally renowned master architects; Louis C . Hess of Hammond, L. Harry Warriner of Gary, Rissman and Hirschfeld of Chicago, J . Ivan Dise and Amedo Leone of Detroit. Many of the houses within the district were constructed by local builders using architect designed house plans made available through mail order catalogs and services such as the Architects Small House Service Bureau. The majority of the district's houses are constructed using styles that reflected the English influence, i.e .: Colonial Revival, Tudor Revival and their smaller cousins the Colonial Revival Cottage and the English Cottage . The district has remained one of the most desirable neighborhoods in Gary since first built. The houses and the landscaping of the present district are highly reflective of the appearance of the neighborhood during its era of significance.