D.C. School Superintendent Floretta D. McKenzie told a House Appropriations subcommittee yesterday that drugs are a "formidable" and "discouraging" problem in the schools and that the number of young people selling drugs may be on the rise.

Noting that adults charged with drug sales face higher penalties than youths charged with the same crime, McKenzie said that unless police can "crack down more effectively on adults," she suspects there may be a temporary "increase in youth activities" as juveniles are recruited to sell drugs.

"Sometimes it is discouraging," she added. "But we now know we must struggle to lower the incidence."

McKenzie's comments came during a hearing on the school system's fiscal 1987 budget. The proposed budget of about $386 million represents an increase of about $26 million over the fiscal 1986 budget.

Last month, six students at McKinley High School, at Second and T streets NE, and one student at Cardozo High School, 13th and Clifton streets NW, were arrested for selling the drug PCP.

Rep. Frank Wolf (R-Va.), a subcommittee member, asked McKenzie and school board President R. David Hall whether the drug problem is getting worse.

Hall responded that it is, "not only in the District but . . . across the country. I don't believe that we have turned the corner. I have not yet seen that our police forces are able to combat the problem."

Hall added that "it is not just a problem of substance abuse. It is an economic problem. People earn so much money so fast from the illegal sale of drugs that offering them $3.50 [an hour] . . . does not compare."

As to the school system, which has cracked down in part by allowing police undercover investigations on school property, Hall said, "Our expectations are to at least be able to guarantee to our parents that their children are going to be safe and free from that element while they're in school."

Hall and McKenzie also said they approve of raising the drinking age in the District from 18 to 21, a controversial proposal that has little support within the D.C. City Council. Both Maryland and Virginia have raised the drinking age to 21.

McKenzie said, "I would not like to think of D.C. as the place where young people come to drink alcohol."

McKenzie testified that the system enrollment was expected to increase by about 1,000 students to 87,676 in the next school year, and that the dropout rate had declined only slightly since last year and now stands at about 16 percent.

She told the subcommittee that the schools have implemented a pilot program to identify students in sixth grade and junior high school who may be potential dropouts and give them special support to keep them in school.