There are a few resources that have really shaped how I approach teaching, specially in a classroom. Here’s a list in no particular order.
The creator of Khan Academy has given a couple ted talks. They have very interesting ideas about teaching and learning in the 21st century.
Andy Ko is a professor at the University of Washington. His talk Learning to Code is sort of a roundup on the current state of teaching in Computer Science. Hint: from what I understood, it’s not good.
Reading Seth Godin’s free book Stop Stealing Dreams openned my eyes to how our current school system came to be.