Over the past 50 or 60 years American educators have tried to turn the public education system into a training ground for leftist thinking. (This started in earnest after WWII while I was still in school.) They want to teach moral relativism, political correctness, and self-esteem in students who have not achieved any real academic success. There's no need to watse time on stuff like math and science. Here are some quotes from prominent educators (I got this from Dr. Santy's blog).

...student attains ‘higher order thinking’ when he no longer believes in right or wrong“. “A large part of what we call good teaching is a teacher´s ability to obtain affective objectives by challenging the student’s fixed beliefs. …a large part of what we call teaching is that the teacher should be able to use education to reorganize a child’s thoughts, attitudes, and feelings.” - Benjamin Bloom, psychologist and educational theorist, in “Major Categories in the Taxonomy of Educational Objectives”, p. 185, 1956

“This is the idea where we drop subject matter and we drop Carnegie Unites (grading from A-F) and we just let students find their way, keeping them in school until they manifest the politically correct attitudes. You see, one of the effects of self-esteem (Values Clarification) programs is that you are no longer obliged to tell the truth if you don’t feel like it. You don’t have to tell the truth because if the truth you have to tell is about your own failure then your self-esteem will go down and that is unthinkable.”- Dr. William Coulson, explaining Outcome Based Education (OBE)-1964

“Every child in America entering school at the age of five is insane because he comes to school with certain allegiances to our founding fathers, toward our elected officials, toward his parents, toward a belief in a supernatural being, and toward the sovereignty of this nation as a separate entity. It’s up to you as teachers to make all these sick children well – by creating the international child of the future”- Dr. Chester M. Pierce, address to the Childhood International Education Seminar, 1973