For an entire morning President Reagan found himself just where Baltimore's leading cheerleader, Mayor William Donald Schaefer, wanted him--within constant view of the new skyscrapers, harbor and homes that federal funds made possible in this aging, port city.

From the moment Reagan stepped from his helicopter onto the grounds of the Baltimore Zoo, Schaefer was by his side, quietly telling him how the city had used past federal dollars to improve and develop parkland. When Reagan strode through the city's own urban enterprise zone in a poor, black section of town, Schaefer was there to say the project was possible only because it received federal and private monies.

And when Reagan finished his speech to county officials on the need to reduce the role of the federal government, Schaefer was there again, escorting the president to the 27th floor of the city's modern World Trade Center for a spectacular view of the Inner Harbor, the centerpiece of Baltimore's federal funds-inspired revitalization.

Later, after hosting a private luncheon for Reagan with some of Maryland's most prominent businessmen and politicians, Schaefer commented: "The president is a great communicator, but every time there was a pause I filled it."

The irony of the day was not lost on Schaefer and those around him. Reagan had come to Baltimore to push his "new" federalism and an economic program that in two years has cost Baltimore and Maryland millions of federal dollars, trimming dozens of social programs and jeopardizing future urban renewal plans. And here was Schaefer, who former President Jimmy Carter once called "my favorite mayor," carefully showing Reagan the legacy of Carter's generous aid policies for inner cities and quietly accepting the president's compliments for Baltimore's progress.

Said one Baltimore official: "It was very odd. Here this guy Reagan is trying to sell a philosophy that is antithetical to us and he's complimenting us for all we've done."

Not only had Schaefer been closely identified with Carter, but he had also been one of the earliest and most frequent critics of Reagan's cuts. In return for that, and possibly for Maryland's support for Carter in the 1980 election, Schaefer felt he has gotten a cool reception from the administration.

But Schaefer was convinced that if Reagan could only see Baltimore, he would want to help, and the city would have a better shot in the future of winning a bigger slice of the diminished federal pie. He had invited Reagan once before but the trip had been cancelled for snow. So when this visit was scheduled, Schaefer went through several days of careful preparation.

He carefully selected the sights to visit. His office printed an artful, graphically-appealing booklet called "Baltimore's Public-Private Partnerships, A visit from President Ronald Reagan." Schaefer arranged the private luncheon for Reagan to meet with political leaders and several businessmen who support Reagan, have helped revitalize the city and recently helped provide funding for some programs cut by the administration.

He made sure there was a breathtaking view of the Charles Center and the harbor, which received $135 million in federal grants. He called in a caterer for a lunch of poached rockfish, lump crabmeat and jumbo butterfly shrimp, followed by fresh raspberries with whipped cream. And then he avoided harsh criticisms of the president or his policies.

"Today you look at things a little differently," said the mayor, after Reagan had departed by helicopter from Fort McHenry, a historic site in Baltimore that may have its visiting hours reduced because of federal cutbacks. "The president honored us with his presence. I didn't want to tell him all my problems."

While boosting the accomplishments of his city, Schaefer said he did remind Reagan during the morning trip that Baltimore, like other urban areas, is facing serious problems. "There are still 40,000 unemployed in Baltimore and 52,000 have been laid off," said Schaefer. "They're still here. They didn't disappear today. But the concern was on other things, the 1,751 jobs the business community came up with."

According to several at the luncheon with Reagan, Schaefer's strategy, which he used on Carter as well, may have paid off. "I truly believe that Don Schaefer got to him Reagan in terms of what has been accomplished in the city," said Republican Robert A. Pascal, the Anne Arundel county executive who is running for governor. "Reagan said how impressed he was with the city. I think when Mayor Schaefer calls from now on he'll get a response."

Although Schaefer avoided harsh criticism of Reagan, others, who attended the National Association of Counties convention and heard his speech today, did not. In his speech Reagan proposed turning over the cost and management of the welfare and 30 other programs to the states. In return, the federal government would take over the cost of Medicaid and food stamps.

"I accept the premise of returning responsibility to the local level, but the idea of using welfare for returning the responsibility is the wrong emphasis," said Montgomery County Executive Charles Gilchrist.

"I think I agree with the man who called it baloney," said Fairfax County supervisor Martha V. Pennino. "This is just rhetoric that sounds good," she said gesturing at the blue-podium in the cavernous convention center where Reagan spoke. "The proof of the pudding is it has not worked to the betterment of anybody. All the programs to help people so they can lift themselves up from their bootstraps have been cut."