A classroom in an elementary school in Nam-gu, Ulsan, where students are engaged in various activities and games. (Newsis)

The average number of students per elementary school class could fall to single-digit levels in 10 years due to ultralow birth rates, a teachers' group said Thursday.

The Good Teachers Movement announced the estimate during a forum held to discuss low birth rates and education reforms, saying the forecast is based on school-age population data that Statistics Korea released in June last year.

According to the worst-case scenario, the average number of elementary school students per class could drop from the current 21.1 to 9.3 in 2033 and 8.8 in 2034, the group said, adding that the figure could fall further to 5.5 in 2060 and 2.7 in 2070.

"The fall in the number of students is too fast now. This could lead to all systems that have been maintained for a long time collapsing at once," the group said, calling for measures to cope with the shrinking student population. (Yonhap)