reporter: the students were not found in a basement as officials initially believed. do you think had there been an underground shelter these lives could have been saved? oh, yeah, most definitely. underground shelters are some of the best things to have in a tornado. reporter: still, there are not enough of them, even in tornado stricken oklahoma. schools aren t required to have underground shelters. the main reasons? the high cost of retrofitting the schools and the porous soil. it s about the money and the statistics. f-5 tornado is very rare, 1% to 2% of the tornadoes. they don t happen very often. it s the very reason they don t have safe rooms for earthquakes, they don t work all the time. reporter: a painful truth for reporter: a painful truth for mikki dickson davis who lost her son kyle at plaza towers. with us living in oklahoma, tornado shelters should be in every school. it should be you know, there should be a place that if this ever happened again during s