EXHIBIT 21 INTERSTATE GENERAL COMPANY L.P. CONSOLIDATED ENTITIES AND SUBSIDIARIES OF THE REGISTRANT DECEMBER 31, 1997 At December 31, 1997, the financial statements of the following entities were consolidated with those of the Registrant in the Consolidated Financial Statements incorporated herein: American Community Properties Trust, a Maryland business trust American Family Homes, Inc., a Delaware corporation American Rental Management Company, a Delaware corporation Brandywine Investment Associates Limited Partnership, a Maryland limited partnership Caribe Waste Technologies, Inc., a Puerto Rico corporation Fox Chase Apartments General Partnership, a Maryland general partnership Headen House Associates Limited Partnership, a Maryland limited partnership IWT Bridgeport, Inc., a Delaware corporation IWT Freehold, Inc., a Delaware corporation Interstate Acceptance Corporation I, a Delaware corporation Interstate General Properties Limited Partnership S.E., a Maryland limited partnership Interstate General Realty, Inc., a Delaware corporation Interstate Waste Technologies, Inc., a Delaware corporation Lancaster Apartments Limited Partnership, a Maryland limited partnership Land Development Associates S.E., a Puerto Rico partnership New Forest Apartments General Partnership, a Maryland general partnership Palmer Apartments Associates Limited Partnership, a Maryland limited partnership Pomfret LLC, a Delaware limited liability company St. Charles Associates Limited Partnership, a Maryland limited partnership St. Charles Community, LLC, a Delaware limited liability company St. Charles Operating Company, LLC, a Delaware limited liability company Sports Realty, Inc., a Delaware corporation Wakefield Terrace Associates Limited Partnership, a Maryland limited partnership Wakefield Third Age Associates Limited Partnership, a Maryland limited partnership At December 31, 1997, the Registrant and its consolidated entities had the following significant unconsolidated subsidiaries: Alturas del Senorial Associates Limited Partnership, a Maryland limited partnership Bannister Associates Limited Partnership, a Maryland limited partnership Bayamon Gardens Associates Limited Partnership, a Maryland limited partnership Brookside Gardens Limited Partnership, a Maryland limited partnership Carolina Associates Limited Partnership, a Maryland limited partnership Chastleton Apartments Associates, a District of Columbia limited partnership Coachman's Limited Partnership, a Maryland limited partnership Colinas de San Juan Associates Limited Partnership, a Maryland limited partnership Crossland Associates Limited Partnership, a Maryland limited partnership ELI S.E., a Puerto Rico special partnership Escorial Builders S.E., a Puerto Rico special partnership Essex Apartments Associates, a Virginia limited partnership HDA Management Corporation, a Delaware corporation Huntington Associates Limited Partnership, a Maryland limited partnership Jardines de Camparra Associates Limited Partnership, a Maryland limited partnership Lakeside Apartments Limited Partnership, a Maryland limited partnership Maryland Cable Limited Partnership, a Maryland limited partnership Monserrate Associates Limited Partnership, a Maryland limited partnership Monte de Oro Associates, a Maryland limited partnership New Center Associates Limited Partnership, a Maryland limited partnership San Anton Associates, a Massachusetts limited partnership Turabo Limited Dividend Partnership, a Massachusetts limited partnership Valle del Sol Limited Partnership, a Maryland limited partnership