Sensory

I work as an autistic support para. One of my students used to do it quite frequently when he started school in the 2016 /2017 school year. He was five years old at the time. He does not do it as much now that he is eight. Actually, this little boy used to grab hold of my calf and hump that. The behavior therapist was in the room at the time, and I asked her "what do I do about this behavior?" There is no normal for behavior that children exhibit. One child might hump their blanket, another may pace, another shake their arms. I would not worry about it if he seems calm and is not bothering anyone. You may want to see if the behavior becomes more aggressive and speak to a professional about the behavior.