Nfhs overtime
 

Where in the rule book does it talk about high school
Overtime?

Page 84 of the 2018 Rules Book.

Be aware, however, that some states use OT procedures that vary from the NFHS. Check with your state for their specific rules.

It's on Page 84, and the title is "Resolving Tied Games". There are notes on how the suggested procedure would affect existing rules, and a disclaimer that your state association may change the overtime procedure.

There seem to be some inconsistencies though. On the one hand, the game ends if the defensive team scores a safety or touchdown, but the ball becomes dead as soon as the defensive team gains possession. How does that work? How can the defense score if the ball becomes dead as soon as they possess it?

The only way for the defense to score a touchdown would be for the defense to recover the ball in the opponent's end zone. The ball would immediately become dead as you point out, but the result of the play would also be a touchdown.

That is possible, but very unlikely. It seems weird that NFHS wants games to end in such improbable fashion, but perhaps they want to give both teams a chance on offense and defense. But then NFHS logic is different from common sense logic ;).

I don't think the rule reflects any NFHS desire for a game to end in any fashion but rather an acknowledgement that it is possible for the defense to gain possession of a live ball in the offenses end zone and that a touchdown in such a situation would eliminate the need for the defensive team that just scored to take a turn on offense. The only way around this would be to contradict the definition of a touchdown, which is possession of a live ball in your opponent's end zone.

Ultimately I think it is a measure to account for something that could happen, however improbable, and if it were to happen reward the team that scored as it feels is consistent with the rules.