(The Center Square) – At a time when school shootings are a concern for many Americans, serious violence incidents are also up in schools across the nation, reports two recent studies.

One study, from the National Center for Education Statistics, shows a 35 percent increase in serious violence incidents in K-12 public schools from the 2015-16 school year to 2019-20. Serious violence incidents include rape, attempted rape, sexual assault other than rape, threatened rape, physical attacks, fights with a weapon, threat of physical attack with a weapon, and robbery with or without a weapon.

More schools responded to the 2019 survey which led to the increase in reported incidents, but the increase was still declared as "statistically significant" by the author of the study.

The 2019-20 NCES study was published in July 2022 and is a look at the latest trends of violence in schools. The violence has also prompted action from state legislatures.

A survey from the American Psychological Association found that 33 percent of surveyed teachers reported experiencing at least one incident of verbal abuse and/or threatened violence from July 2020 to June 2021.

The National Education Association President Becky Pringle called this increase a “crisis” in a news release.

“This crisis of violence should unite educators, students, families, and politicians around the common goal of ensuring that our public schools are the safest, healthiest, and most just places in our communities," Pringle said.

Ke Wang, the researcher from the American Institutes for Research who co-authored the NCES 2019-20 study, said that the increase in those incidents is significant.

“For serious violent incidents, you can indeed say that the number has increased between 2015-16 and 2019-20. I just tested this out and the increase is statistically significant,” Wang said.

In 2015-16, there were 40,800 incidents reported by 12,900 participating schools. In 2019-20, there were 62,800 incidents reported by 21,100 participating schools.

Wang said that although the number of participating schools varied, the years can be compared "apples-to-apples."