''A teacher affects eternity; he can never tell where his influence stops,'' Henry Adams wrote in his autobiography. For many of today's teachers, however, their influence has a new and painfully sharp boundary: the computer keyboard. It is a barrier that a newly formed organization, the National Computer Training Institute (NCTI), hopes to help teachers surmount by ''using teachers to teach teachers about computers.''
Surveys have repeatedly shown that the vast majority of the United States public thinks children should be taught how to use this new electronic tool. Due to the tremendous societal pressure, American school systems have rushed to acquire small computers, and they have gotten their hands on an estimated 600, 000 machines. Yet as few as 5 percent of the nation's 2.4 million kindergarten-through-12th-grade teachers appear to have themselves gained a modicum of computer literacy.
This educational stampede for getting computer hardware first, and figuring out how to use it later, has been criticized by Secretary of Education Terence Bell and the Carnegie Foundation for the Advancement of Teaching, among others. While computers represent a significant new educational resource, there appears to be a widespread misconception ''that by thrusting a bunch of computing equipment into a school system somehow people are automatically getting a much better education,'' objects Dr. Alan K. Cline of the University of Texas at Austin.
Before computers can be intelligently integrated into the educational system, teachers themselves must understand what computers are all about, argues NCTI's founder and president, Bruce Frederickson.
Some computermakers have tried to help alleviate this problem. Tandy Corporation's Radio Shack offers teachers 20 hours of its standard computer classes at no charge. And a number of companies like IBM and Hewlett-Packard provide training along with the computers they donate to selected schools. Also, there have been a number of local efforts to provide teachers with computer instruction.
But Mr. Frederickson felt more was needed. So the teacher-turned-businessman left the Learning Institute, one of the nation's largest private teacher-training organizations, to establish a nationwide network offering computer training tailored for teachers.
The basic principles behind NCTI are these:
* The use of computer-literate teachers as instructors. This serves two purposes, Frederickson says. Teachers accept new information more easily from other teachers. The pay the teacher-instructors receive will supplement their low salaries and keep them in teaching.
* Offering a substantive, 45-hour course taught on evenings, weekends, and in the summer. The intent is not to tell teachers how to use computers in their teaching but to make them computer literate so they can make up their own minds about how best to use the machines. Topics covered include: word processing and helping students write, evaluating educational software, educational applications of information management tools, computer graphics, introductions to the programming languages BASIC and LOGO, curriculum issues, school planning, and telecommunications.
NCTI is currently negotiating with 90 universities for accreditation. This will allow the course to count toward advanced degrees and aid with individual teachers' career advancement. The program has already been accredited by the University of California at Berkeley.
* The course will come with a money-back guarantee. The basic cost of the program is $195, with an additional $10 to $70 if it is taken for credit. But if a teacher is not satisfied with the quality or usefulness of the class, he or she can ask for a full refund.
The new institute has the enthusiastic backing of the International Business Machine Corporation. IBM bankrolled the project and is providing 15 of its PCjr computer systems for each classroom.
''We are very excited about this program.... Over the past few years we have evaluated a number of proposals, and Bruce's was by far the most organized and thoughtful,'' says IBM's Robert Wallace.
Despite the Big Blue connection, the course is ''generic,'' and NCTI will not supply the computer giant with the names and addresses of those who enroll, Frederickson emphasizes.
In its first year, the organization hopes to train 24,000 teachers. Those teachers interested in more information may call 800-426-NCTI or, in California, 800-626-NCTI. From Hawaii or Alaska, call NCTI collect at (415) 797-9010.