I've been using ClassDojo for about 9 months now and I think it is one of the best FREE resources that I have found. You just create an account and you have access to some great teaching tools. I had been using ClassDojo to teach students about Mindset and then they came out with the Perseverance series and most recently the Empathy series. I use these short video clips ALL THE TIME and students LOVE them. You can check it out HERE.
Growth Mindset (5 videos in the series plus 2 activities)
Perseverance Series (3 videos in the series plus a follow up activity)
Empathy Series (3 videos in the series plus a follow up activity)
Be sure to check out the resources page for posters, coloring pages, etc.... This may be more useful for classroom teachers but there are a few things that I have printed off:)