How do you react to creative thinking?

I encourage you to watch the following YouTube video and reflect on your practice.

This video speaks volumes to me.  In the past, when I witnessed a student doing something out of the ordinary, I would ask the student to "get back in line".  Over the last 2 years, I have changed my outlook on creativity in the classroom.

I truly believe it is the reaction of the adults, or teachers, which can determine the outcome of the amount of creativity in a school.  As Mararu Ibuka would say "Creativity comes from looking for the unexpected and stepping outside your own experience"

Currently, I try to encourage students to "step outside the box" and try to complete math in a way that makes sense to them.  I also struggle greatly with the idea that "math can only be assessed by a traditional exam". 

If there is one quote of creativity which inspired me to change my teaching practice it is "Creativity has more to do with the elimination of the inessential than with inventing something new" - Helmut Jahn

I now ask you:

How do you react when you see something "out of the ordinary"?

How do you allow for true differentiation of an individual in your class?