It’s 8:32 a.m. on a Thursday morning and Coppell High School history teacher Joshua Chanin wears a bright smile on his face.   His room, adorned with vital aspects of his identity - a photo frame with Queen Elizabeth, a photo gallery of his students, a notable wall of the 46 U.S. presidents - has become an appendage of him. It is not always easy to know if a teacher enjoys their subject, but in the case of Chanin, it’s glaringly discernible.