There are six NFHS rule changes for the 2017 season:
Only a goalkeeper can be in the crease to block a shot.
Playing without required mouthpiece will now be a technical foul (30-second penalty or change of possession) rather than a non-releasable foul.
Stalling rules now are in effect in the last two minutes only if the score differential is four goals or less.
Since ground anchors are not typically used on grass fields, Rule 1-3-2a was modified to allow, but not require, the use of ground anchors if a flat-iron goal is used on a grass field.
Rule 4-3-3 (introduced last year) previously called for tape to be applied to the handle of the crosse for any player taking a faceoff. With new handle materials now available that are more durable than tape, the committee revised the rule to allow for use of new materials.
A change in restarts after a foul during a face-off. Previously, if a player or team committed a foul before or during any faceoff, the ball was awarded to the offended team in its offensive side of the field at the center. The rules committee removed "or during" from Rule 4-3-1 (Exception 2) in order to be consistent with Rule 4-4-2, which calls for a restart from "the spot where the ball was when play was suspended."