This is an OpenSCAD Version of the NIH Surgical Mask Tension Release Band located here:
There are a few others who have remixed this, so for this purpose, I took the original file from the above site, and rebuilt it in OpenSCAD.
The idea here being: The one-size-fits-all is fine for a temporary solution, but since kids are going back to school, and more and more folks are going to be wearing masks for a longer period of time, why not create the size/style best suited for you. You can create a single hook to save material, especially since you can customize the size of the strap itself.
If we are in this for the long haul, no reason to be using generic solutions. Make your own for yourself, your kids, your team/employees.
In the Customizer you can also choose to add Text to the back rather than a Cutout back plate.
A few of the possible combos are included, Basic/Adult/Teen/Child. But you are encouraged to print one, and then use Customizer to print one specific for you or your needs.