Portola Valley, Calif. — Fifteen years ago, Ann Piestrup says, she quit her job teaching fifth grade in Buffalo, N.Y., frustrated because the traditional classroom situation was stifling development of the potential she knew her ''poverty area'' pupils possessed.
Today her firm, the Learning Company, is the acknowledged leader in a fast-developing field - the use of computer ''learning games'' to help children develop conceptual skills. It produces microcomputer software for use at home or in school by children aged 3 to 13.
Founded in 1980 by Dr. Piestrup, who is chairman of the board, the Learning Company (TLC) put its first two programs on the market last March. By the end of the year the company was producing six other learning games and had hit the million-dollar sales mark. Its products had also won two major education awards - Learning magazine's ''Software of the Year'' citation for 1982 and No. 2 ranking in Info World magazine's listing of the top 10 software programs for 1982. TLC's Rocky's Boots, for children aged 7 and up, was the only educational program in the group.
More than a decade of research - starting at the University of California in Berkeley, where she specialized in ''child thought and development'' and earned a doctorate in educational psychology - led Dr. Piestrup to her present situation.
In that period she worked with students at every grade level from kindergarten to college in an attempt to find out ''what was successful in learning.''
Simply put, she explains, ''involvement'' and ''interaction'' are keys to awakening children's innate abilities. Dr. Piestrup was selecting and packaging the best educational material from among books, teaching aids, videotapes, and other media when she became aware that such material was not readily available for parents who might wish to encourage learning at home.
Computers have been used in teaching since the early 1950s, but most programs simply tried to duplicate traditional teaching methods - presenting information, asking questions, indicating whether the answers were right or wrong.
Dr. Piestrup says she learned that computers ''are interactive and personal, '' and are ''attentive listeners that respond quickly.'' She points out that the ''learning games'' her company produces rely on color, music, and a playful approach.
With more and more manufacturers producing color microcomputers (spurred to some extent by the popularity of video games), prices were slipping below the $1 ,000 level.
In 1979 Dr. Piestrup founded Advanced Learning Technology, with grants from the National Science Foundation, National Institute of Education funding, and the Apple (computer company) Education Foundation. Working with several computer programmers, she developed ''learning games'' that proved immediately popular with preschool and elementary-school children who ''tested'' it. Parents and educators also responded favorably.
With some $300,000 in private funds from Melchor Venture Management of Los Altos, Calif., Advanced Learning Technology became the Learning Company and moved into its present quarters in Portola Valley (just west of Palo Alto). Its first two programs - called Moptown and Magic Spells - were designed for use with the popular Apple II microcomputer and marketed through Apple.
Now TLC makes programs that can be used by Atari and Tandy (Radio Shack) computers, and plans to have programs that can be used on other leading home computers.
Besides selling its programs directly, TLC has agreements with 14 distributors, including all the largest ones in the United States, Dr. Piestrup says, and has been approached by major textbook publishers and toy distributors. The programs are also to be marketed through some of the nation's large discount chains, such as K mart.
The learning games produced by TLC and a few other companies share color, sound, and challenge with the popular games that are spurring the boom in home computer sales. But they lack the violence - the blasting, burning, and devouring - and the win-lose aspect of the video games. Ann Piestrup says these video games will soon be passe, and she is confident they will be replaced in many homes by meaningful, educational games.
There are no losers in TLC's games, no right or wrong, no good or bad performance - no dead ends. Each child is ''challenged to think logically by developing ideas out of experience.''
All programs designed by TLC's staff of some dozen researchers and programmers are tested in homes and schools, nursery schools, and learning centers. Dr. Piestrup's home itself is a ''test center,'' with her five-year-old daughter and neighborhood children vying for time at the controls.
Through a ''building-block structure,'' the programs guide children through progressively more difficult challenges. Concepts learned are built upon to acquire more-advanced concepts. In the more-advanced programs, the user can create variations on the basic games and even devise new ones.
Dr. Piestrup recalls one youngster who, after testing one of the more advanced games, declared it ''better than Pac-Man.'' Another declared, ''It makes me think.''
At Skyline Elementary School in Daly City, Calif., pupils in all grade levels use TLC programs. Beverly Saylor, a fifth-grade teacher, says the learning games are ''excellent, and the kids just love them.'' She says that although the games have been in use for less than a year, she can already see how they have increased the ability of some of her pupils to think logically.
Upwards of 20,000 TLC learning games, priced from $45 to $75, have been sold so far to homes and schools in the United States and overseas. Dr. Piestrup says she has received letters from users in Upper Volta, Africa, and Papua New Guinea.
Drawing the line between gamesmanship and learning is an inexact art, she admits, and it could become a problem as more companies try to enter the ''learning games'' market. Thorough testing, she emphasizes, is the cornerstone of quality control for TLC.
Ann Piestrup has not forgotten her original concern about reaching children from deprived backgrounds. She says that through classrooms, libraries, and other outlets, many will gain access to microcomputers.