Baby Bear Does Something to His Ceiling Fan

Another entry for the "How in the World Did He Do That?" file:

I heard intermittent banging noises coming out his room last night. There's really nothing so unusual about this, at least for Bear. When he's not rearranging his furniture, he likes to empty his toy box, then lie on his back on the bed and balance the toy box on his feet, flipping it around till he finally kicks it across the room till it hits the wall. He also enjoys kicking the wall just because he has feet and it's there.

Still I felt compelled to check on him every so often. Each time I did, the toy box was still in the corner, filled with toys, while the furniture remained in the same configuration as the last time I looked. Instead of the toy box, Bear was on his back balancing and bouncing this 22-inch sensory ball on his feet:

Then I finally noticed something odd about the ceiling fan directly over him. It was still spinning, but the blades didn't look right. Only after I shut it off did I see that all five of them were somehow bent up toward the ceiling at greater than a 45 degree angle, but at less than 90. (That is, I think it's more than 45 and less than 90. The only D to ever mar my report card was for geometry in 10th grade).

But how could he have done this with that lightweight ball, without hurting himself or damaging the ball?

Only he knows, and as usual, he ain't talkin'.