IND vs NE

[sm_bbcoach]

Wondering if anyone can clarify for me what the exact call was for this play:

Manning under center. Gets up (as he had done all game) to call an audible. This time though, he walked towards the left sideline, waving his hands. The ball was snapped to the running back.

Is this another version of the "sleeper" trick play. It is agianst the "spirit" of the game or is there a NFL rule about this?

Would this play be allowed to go off in NFHS games?