Since elementary school, a doctor was all 17-year-old Harvey Carey of Chicago ever wanted to be--until this summer.

As one of 210 minority high-school students in the Leadership Education and Development (LEAD) program, Carey says he is giving business a second look, because he was encouraged to see that more minorities are making it to the top in business than he had believed.

Carey's response is perhaps everything originators of the three-year-old LEAD program, whose participants are visiting Washington this week, could have hoped for.

A recognized paucity of minorities in the leadership of U.S. business spurred development of the LEAD program, which sells the concept of a business career to selected students from around the nation. This year's participants include nine from the Washington area.

Students apply through A Better Chance Inc., a Boston firm that places minority students in preparatory schools, and those selected take part in four weeks of courses, field trips and case studies at one of seven universities. arold M. Daniels, assistant director of admissions at Northwestern University, one of the participating schools, said minority students often do not realize the opportunities they have in business, nor do they have any role models from their ethnic group. It is LEAD's purpose to provide such guidance.

"We want to expose them to the type of businesses that are truly high-quality businesses," said Peter J. Scarperi, president of the program.

Judging from data gathered so far for the program, which began in 1980 at the University of Pennsylvania, about half of the 240 LEAD alumni, not including this year's class, are studying a business curriculum if they are in college, Scarperi said.

About 600 students applied for the program this year, with the largest percentage coming from New York, California and Texas, spokesmen for LEAD said.

Data from last year's group of 30 students show an ethnic breakdown of 81 percent blacks, 10 percent Hispanics and 9 percent Asian-Americans.

Although 60 percent of the participants come from inner-city schools, the LEAD program is not aimed exclusively at economically disadvantaged teen-agers, spokesmen said. The remaining 40 percent come from private schools, they said.

Corporate sponsors, this year numbering 75, finance the program, aside from room and board costs, which some of the universities provide. Fundraising this year gathered about $500,000, LEAD officials said. EAD alumni are achieving a measure of success, with all of them attending or planning to attend college. Ivy League schools have taken in 44 percent of the students, LEAD representatives said.

For students, the program is useful because of the responsibility it teaches, the network of contacts made, and its role in showing what opportunities are available, said Patricia McIntosh, a participant from Brooklyn.