Before I started teaching at a Finnish public school, I taught first graders in Arlington, Massachusetts. And I had a sharp-eyed mentor teacher named Joanna.
"Psst. Can I speak with you for a second?" Joanna pulled me aside during a lunch break. She wasn’t wearing her characteristic smile. "Tim, please don’t be offended by what I’m about to say, but whenever I peek into your classroom, you always seem to be sitting down with your first graders on the rug." The criticism stung—not because it was off-target, but because I knew it was true.