It appears the last school shooting in Wyoming was with a bow and arrow.
http://www.examiner.com/article/two-school-shootings-within-hours-of-each-other
And this one many years ago...
http://en.wikipedia.org/wiki/Cokeville_Elementary_School_hostage_crisis
And that bow shooter was full-on crazy train. Aspberger’s Syndrome. Hated his father for fathering him. Said in his suicide note that his father should not be allowed to reproduce - ever.