A bill that would grant subsidies for reduced school fares on the Metro subway system was introduced this week in the D.C. City Council.

Sponsored by council members Hilda M. Mason (Statehood at large) and Wilhelmina Rolark (D-Ward 8), the measure would provide subsidies for District residents only. The bill would require students to pay fares ranging from 10 cents to 20 cents for each subway ride. Within the District, adult fares now range between 40 cents and 85 cents.

Students would have the same transfer privileges as adult subway riders --a free transfer from rail to bus, but no transfer from bus to rail.

Under existing law, school subsidies are paid for students traveling on Metrobuses but not on the subway.

Mason, a former school board member, said in a statement that the extension of the subway's Red Line to Silver Spring last month resulted in many bus route changes. These changes made it difficult for many students to get to school by bus and expensive for others who ride the subway at full fare, she said.

Under existing law, tokens are sold for 10 cents each to D.C. public and private schools students who live in the city. The city government subsidizes Metro for the difference between each token collected aboard a bus and the amount of a full adult fare Last year, the subsidy totaled $3.7 million.

Betty Ann Kane, a member of the school board who organized a demonstration by subway-riding students at the Takoma station last week, said there are no reliable figures on how many students would use reduced rail fares.

"I am convinced it is not going to be a whole lot of money," Kane said.

About 30,000 students now ride buses to and from school, she said. District schools do not provide the kind of school bus service that is common in the suburbs.