These guys say ncaa and fed is the same on this question.
NFHS Forum: Pylon plays
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First of all, the Fed rules and the NCAA rules regarding placement and interpretations on plays where a ball touches a pylon are identical. The actual wording of the Fed rules are precise w.r.t. placement of the pylon, but aren't too much help when it comes to ruling on the interaction of a ball with the goal line pylon. They carefully say that the pylon is out of bounds, but they also say in case play 1.2.4 that if the pylon is properly placed, the ball would have to penetrate the plane of the goal line before touching the pylon.
The NCAA rule is much more definitive: "A ball that touches a pylon is out of bounds behind the goal line." PERIOD. Note, they don't say "...behind the goal line EXTENDED." They say goal line. Is it? Well, not really, but it's an accepted convention to keep us from having to split hairs. Consider a punt that rolls toward the pylon. If it rolls into the pylon's front face, chances are that it actually crossed the inside edge of the sideline at about the 1" line. Are you going to place it there?
In order to avoid these kinds of problems, both the Fed and NCAA have consistently published rulings that say that a ball, loose or in player possession, that touches a pylon is considered to have touched it in the endzone.