There has been, on average, 1 school shooting every week this year - CNN

We're only 20 weeks into 2018, and there have already been 22 school shootings where someone was hurt or killed. That averages out to more than 1 shooting a week. ....
https://www.cnn.com/2018/03/02/us/school-shootings-2018-list-trnd/index.html