I think the point where schools kill creativity is high school. The reason I think this is because high school is the point where your thoughts and opinions don't matter as much and it's mostly about fitting as much facts and information on specific subjects in your head to prepare you for post secondary studies. In elementary school creativity was encouraged way more than in high school. With most of the activities being such as: "Draw what you want to be when you grow up" or "how does your dream house is going to look like". A few days ago I saw my younger brother drawing some pictures of spaceships and monsters. So then I decided to draw as well since I haven't done that in a long time, but I could not come up with anything to draw. Back when you were younger you had to use your imagination a lot and now it's mostly about learning things straight out of a book, eventually shutting down your creativity and your imagination that makes each one of us unique, that's why I think schools kill creativity.
"Why Schools Kill Creativity" http://www.youtube.com/watch?v=zDZFcDGpL4U