Killing creativity?

What can I say...I love TED Talks! I can honestly say that I've never seen a bad TED video. I was viewing a Khan Academy video and clicked on a recommended video which featured Ken Robinson (http://www.ted.com/playlists/24/re_imagining_school.html). While his video is not math-specific, it casts a light on what is happening to education. Robinson argues that we are no longer educating the 'whole' child- we use children to fulfill an image that we already have of them. We do not let children control who they become. He argues that all children are born artists, but struggle to remain that way. Children are so afraid of being wrong that they stop taking risks...they stop having wishes and start having goals.

The definition of education has changed. This generation will produce more high school and university graduates than ever before, but professional degrees don't mean employment anymore. Everyone seems to be educated, but few really stick out. 

Robinson's theories ring true in my classes- especially math. Children are so afraid of being wrong that they often don't participate in class or do their homework. They would much rather commit to nothing than the wrong answer. I also teach science and students seem to be more capable of forming and testing a hypothesis...but if I ask them in math, they are incredibly reluctant. Students have it in their minds that there is only ever one answer, and if they don't definitively know that answer, they are wrong.

My question is, how can we teach creativity in high school? How can we awaken that inner child, who still believes in figuring things out and taking chances? While our math answers should be accurate, often finding them means being wrong a few times. How can we encourage students that's it's okay to be wrong?