I retired a few years ago after 43 years as a Hawaii public school educator, so I am familiar with the required as well as elective courses over the course of my career.  I agree, most teachers do stifle their opinions, so to speak, but the few that don't cause lots of trouble on issues ranging from race to gays to religion.  I think all those other disciplines/focuses need be separated from history. They can be integrated with history study, but often history is sacrificed to the more current and emotional issues which engage students but are divorced from historical background or anything that happened before the students were born.  Ask today's high school students what they know about 9/11.  There is a reason so many students don't know in what century our Civil War was fought or have no sense of an historical timeline.  Europe is the cradle of our American culture, but European History was deleted from my school's curriculum years ago to make room for "social issues."