Secretary of Education Terrel H. Bell yesterday repeated the Reagan administration's call for basing teachers' salaries on performance and he suggested that Arlington County, where Bell's son is a 7th grade student, be one of the first public school systems to adopt the controversial program.

"We're not getting our fair share of the top level talent to go into teaching," Bell told a traditional back-to-school gathering of Arlington's more than 1,000 teachers and classroom aides. "We have to turn that around. The question is what should we do about it."

In his speech, Bell carefully avoided using the term "merit pay," which has drawn fire from the nation's teachers unions, and said instead outstanding scholars could be attracted and encouraged to stay in teaching through what he called an "academic ranking" system. But the difference between the two plans was unclear and some teachers, many of whom were wearing buttons that said "Merit Pay/Not Today," said they were not fooled by Bell's language.

"What he was still saying is merit pay," Florence Rossi, a social studies teacher, said. "He's just trying to soften the blow."

Other Arlington teachers supported the administration's pay-for-performance ideas. "I was all for it," said high school Latin teacher Sally Davis, who said she favors rewarding accomplished teachers.

Virginia Gov. Charles S. Robb has already endorsed a $500,000 master teacher pilot project that would be established in some state school districts before implementing a master teachers program statewide.

"I'd like to see a middle-sized school system like Arlington explore this," Bell said.

Virginia State Department of Education officials said yesterday that no school systems have been targeted for possible inclusion in the proposed state-supported master teacher pilot project. But Arlington officials have already begun looking at the possibility of instituting their own master teacher system.

Arlington School Board Chairman Simone (Sim) J. Pace has already voiced support for a master teacher program and at a meeting tonight the board is expected to instruct staff to develop a draft plan for Arlington.

After his speech, Bell told reporters that the Reagan administration was not endorsing merit pay for teachers, which generally means a system in which principals decide which teachers get higher pay based on classroom performance. Bell said the administration does favor academic ranking, also known as a "master teacher plan," in which a committee of faculty members or school administrators would decide which teachers to promote to higher pay levels.

Bell has said that he favors peer review rather than evaluations by principals alone, who teachers have complained could be biased for or against certain employes.

President Reagan reaffirmed his support of a master teacher system after a recent discussion between the two, Bell said. Bell told reporters yesterday, "I don't think you're ever going to get teachers to accept merit pay."

It was the second time Bell has addressed Arlington school employes in recent weeks. Last month, he spoke at a private conference of Arlington school administrators and presented virtually the same message at the request of Superintendent Charles E. Nunley. "I think he wanted to see if I could tell the same story twice," Bell quipped as he began explaining the academic ranking system to the teachers yesterday.

After the program, school spokesman Dennis Smith said he thought Bell was interested in the Arlington school system, which has 14,000 students, not only as a parent but also because he sees Arlington as a testing ground for the administration's ideas on education.

"His son goes here and he's very active," Smith said. "He's using it as a base. He thinks we have a good-sized system to implement his views."