Cont. Clock Start After Time-Out on Free Throw

[nine01c]

Just curious, but is it actually NFHS option? For example the "optional" coaches box is explained and described in the NFHS rule book Rule 1-13. My state uses it.

Massachusetts has several deviations from NFHS that the MIAA has chosen to modify on their own. As far as I know, there is no mention of these as being NFHS options. They are:
1) games are two 16 minute halves
2) five 60 second time outs per game
3) 30 second shot clock
4) no 10 second count in backcourt (girls only)
5) requires players wear mouthguards on court

I consider these as non-NFHS modifications that my state has taken liberty to use (their right to do so, I guess).
I suspect the Mercy Rule falls under the same category in states that use it. What are some other deviations states use that differ form NFHS?