Too many children in one classroom diminish the quality of education, say Utah teachers who rated overcrowded classes as their number one complaint in a Deseret News survey.

A statewide average doesn't tell the whole story about how many children are in classrooms in Utah's schools. Where you live in the state may make a considerable difference in the number of children one teacher has in the classroom.Statewide, according to the 1987-88 report of the State Office of Education, the average pupil-/teacher ratio for that school year was 25.01.

However, there are extremes at both ends of the average, ranging from 12.95 in Daggett School District to 28.04 in Washington District, where sharply rising population has contributed to school growth.

Among the 40 districts, seven have ratios under 20 and 12 greater than 25. In general, rural districts have smaller student/teacher ratios and urban districts along the Wasatch Front greater ratios.

The ratios also may be misleading in regards toactual class size because they include interns and overlook some other actual teacher load factors, said Laurie Chivers, financial officer for the state office.

For instance, she said, a high school teacher may teach seven classes a day with 30 students in each class, then have an eighth period for preparation. The average would include that extra period, bringing the ratio down to 26.1, although the teacher actually deals with 30 students in each of his classes.

The ratios also include special education classes. Self-contained classrooms for handicapped youngsters may not exceed 12 to 15 students based on federal guidelines.

Teacher/pupil ratios in Salt Lake County school districts in 1986-87 included: Granite, 25.89; Jordan, 25.30; Murray, 26.57; and Salt Lake, 22.19. A population shift to the south end of the county is creating more pressure on south valley districts to find room for more students.

School officials are concerned that the number of classrooms with 30 or more students is growing. From the 1986-87 school year to the 1987-88 year, the number of classes exceeding 30 increased from 2,089 to 2,436 at the elementary level, says a report compiled by the Utah Education Association.

Much of the increase is occurring in the primary grades, where individual instruction is deemed by teachers to be most critical.

Not everyone agrees that class size is the major factor in the quality of education, but for teachers at least, it is the first and foremost concern.