In the wake of those threats, ABC13 Investigates wanted to understand what drives this sudden increase in threats and guns found in schools.
After the school shooting in Parkland, Florida, reports of school threats in the days after jumped 300 percent.
On a normal day, 13 threats are reported. In the week following the Parkland shooting, at its peak, 107 threats were reported in a single day, according to data compiled by the Educator's School Safety Network.
Researchers in 2015 found "significant evidence that mass killings involving firearms are incented by similar events in the immediate past," adding that events often happen within the following 13 days.
FBI data shows the number of incidents is going up as well. From one reported active shooter incident inside a school in 2000 to 30 reported in 2017. In 2014, 2015 and 2016, each year reported 20.
Texas data shows reports of guns in schools is on the rise too, up 58 percent since 2014, but follows a fairly steady trend line over the last 10 years, according to Texas Education Agency data.
The same data shows no firearms were reported in Santa Fe ISD since the 2005-2006 school year. Houston ISD, the state's largest district, averages about 10 gun reports a year. Last school year, there were 12.
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