Jo Boaler, the Stanford professor behind YouCubed.org, works hard to dispel fixed mindsets about math. She recently shared a video from the 2015 YouCubed summer camp in which her students show their enthusiasm for problem solving and their willingness to learn from their mistakes.
For those of us trying to promote a Growth Mindset, particularly regarding math, this video is a great resource. I also encourage you to take a look at the YouCubed.org website for more great materials, including the “Week of Inspirational Math,” which would be a great way to start off your school year.