Wikipedia has a source for the “lockdown kitty litter” concept mentioned above:

The only known official instance of cat litter being placed in school classrooms for potential use by students was in the late 2010s by the Jefferson County Public School District in Colorado, where the 1999 Columbine High School massacre took place. Some teachers were given “go buckets” that contained cat litter to be used as a toilet in an emergency lockdown situation, such as during a school shooting.[4][43][44]

Weird, but I suppose it’s sensible. Better than having kids pee themselves in an extended lockdown.