Free fall is not a force!Your letter does not really explain why Granny shouldn't worry, why not? cat will go faster and faster!Also, what is the difference of having the cat pushed down? does it make the cat accelerate more? it's not clear.
I really like your glogster.The Free Fall video and the cat images are coool :P . But maybe you should focus on the story more. I would also recommend to write one equation with and one without initial vertical velocity. In your glogster the vo component is useless if you dont have an initial velocity.
In your glog with the picture of the ball falling I would mention how position varies directly with the square of time. Otherwise great glog!