While probably appropriate for a shooting, "when shit's going down, call the government first" is generally not a terrible way to handle things as an adult as it tends to reliably turn N-figure problems into much more complicated N+1 or N+2 figure problems. Running your situation by a cooler head not immediately involved is almost always better and the government is always slow enough to show up that you don't lose anything if you do go that route.

Likewise, I think it is very ill-advised to cram kid's heads full of "dial 911" at the young vulnerable age where repeated messaging goes into the kind of memory that's all but impossible to overwrite.