Congressional Democrats bluntly accused President Reagan yesterday of twisting the truth and trying to palm himself off as a champion of better schools with a campaign of "gross misrepresentations" and "grotesquely inaccurate" statements.

"It embarrasses all of us as Americans to have to point out that the president of the United States is not telling the truth," House Majority Leader James C. Wright Jr. (D-Tex.) said at a news conference. "It's an embarrassment to any of us to have to state that fact. But the fact has been repeated so frequently that it must be called to the public's attention."

Sens. Edward M. Kennedy (D-Mass.) and Claiborne Pell (D-R.I.) and House Education and Labor Committee Chairman Carl D. Perkins (D-Ky.) joined in the attack, accusing Reagan of repeatedly mangling educational facts and figures in recent weeks and of playing down his attempts to dismantle federal aid programs.

"The president's advisers obviously hope that on the issue of education, the American people will watch what he says, not what he does," Kennedy said. "In the three annual budgets submitted since they came into office, this administration has called for cuts in education amounting to $9 billion, or almost 20 percent of the federal education budget for those years. In everything they have done, they have proved that they are no friend of teachers or students, schools or classrooms."

Perkins was especially annoyed by what he described as Reagan's "policy" of "making all these false claims about federal interference" in the schools, a theme the president sounded again Thursday in Hopkins, Minn., in defense of his educational policies.

Speaking at a regional forum of the National Commission on Excellence in Education, Reagan said that the federal government "provides 8 percent of the educational budget, but . . . has, kind of, grabbed off about 50 percent of trying to regulate the schools."

Perkins, one of the architects of the federal educational support structure, denounced such talk as "just nonsense."

With education emerging as a major issue for the 1984 campaign, Reagan has been advocating merit pay for top-flight teachers as the centerpiece of his program. Perkins said he was all for that, but as a former teacher who earned $59.60 a month he added that "we've got to pay ordinary teachers more, too."

Even today, Perkins said, "we have many $11,000 and $12,000 teachers, in some cases as low as $10,000," while starting salary on a Ford Motor Co. assembly line is $20,000 to $21,000.

Wright said it was "grotesquely inaccurate" and "outrageous" for the president to say," as he did in a May 17 news conference, that federal aid to education had increased "2,000 percent" in a 10-year period, from $760 million to $14.9 billion.

"Ten years ago," Wright said, "the federal budget for assisting and aiding educational programs was not $760 million, but very nearly $7 billion. And so he Reagan has totally skewed the facts in his misrepresentation.

"I want to believe that he doesn't know any better," Wright said. "I want to believe that those who furnish him those spurious statistics are the culprits and that the president of the United States is innocently making these statements, not aware of their total untruth."

Wright also took exception to Reagan's repeated assertions that education receives more dollars than defense. Apparently comparing the federal defense budget with all kinds of spending for education, including local, state and private outlays, the president said Thursday that "in 1982, the total budget for national defense was $179 billion" while "it was $215 billion for education."

"That's another inaccuracy," Wright charged, saying the president was even counting private costs, such as baby-sitting expenses while a parent attends a college class. He said that Reagan also failed to mention he is seeking $245 billion for defense this year.

Pell noted that the administration has made "drastic cuts"--$200 million between fiscal 1981 and 1983--in the higher-education grant program for low-income students that bears his name, and also in the direct student loan program, which dropped by $107 million between 1980 and 1983.

"Had President Reagan had his way, education programs would have been cut even more," the four Democrats added in a joint statement, pointing out that Congress had fended off much larger reductions proposed by the administration.