The author has written profoundly and truly about the motives and rewards of teaching. I agree that merit pay for a few teachers is not only inappropriate, but could be harmful. Since there is no objective scale for measuring excellent teaching, administrators who decide who has earned merit pay could easily be fooled by window dressing. Whether or not the decision is fair, the resulting resentment and cynicism on the part of other staff members could seriously threaten harmony and lower morale.From my experience as a teacher, I suggest these ways of improving the quality of teaching in schools: lighter teacher loads, administrative firmness in handling incorrigible students, help on paperwork, and less patrol duty. There are also many small ways of making a teacher feel wanted and appreciated. They, too, will encourage success in a difficult job. Jean Trigg, Henderson, Ky. Letters are welcome. Only a selection can be published, subject to condensation, and none acknowledged. Please address them to "Readers Write," One Norway St., Boston, MA 02115.