Perhaps this is approximately true if you focus exclusively on mass shootings at schools. But shootings overall are one of the leading causes of deaths for children in the US.
See for instance the CDC's visualizations on causes of death per age group [1]. In 2020, 476 children aged 10-14 died in traffic accidents involving motor vehicles. 218 children aged 10-14 were killed in homicides by firearms.
Those two numbers are very much in the same order of magnitude. This is also the case in prior, non-Covid years.
> Wer durch die Leistung eines anderen oder in sonstiger Weise auf dessen Kosten etwas ohne rechtlichen Grund erlangt, ist ihm zur Herausgabe verpflichtet. Diese Verpflichtung besteht auch dann, wenn der rechtliche Grund später wegfällt oder der mit einer Leistung nach dem Inhalt des Rechtsgeschäfts bezweckte Erfolg nicht eintritt.
> A person who obtains something as a result of the performance of another person or otherwise at his expense without legal grounds for doing so is under a duty to make restitution to him. This duty also exists if the legal grounds later lapse or if the result intended to be achieved by those efforts in accordance with the contents of the legal transaction does not occur.
See for instance the CDC's visualizations on causes of death per age group [1]. In 2020, 476 children aged 10-14 died in traffic accidents involving motor vehicles. 218 children aged 10-14 were killed in homicides by firearms.
Those two numbers are very much in the same order of magnitude. This is also the case in prior, non-Covid years.
[1] https://wisqars.cdc.gov/data/lcd/home