Many times a student will question WHY do we have to learn this? You have more or less answered your own question - teachers do have a curriculum to follow but understand that it is very broad in nature and can be interpreted and taught in any number of ways. This is done on purpose. The curriculum is very flexible so that most all teachers will feel comfortable teaching from it. If you feel that your class is not learning the same as, say your best friend's class with another teacher, it is most probably because teachers, like students, learn and teach to their own strengths.
What this means is this - you are learning all the same stuff that any other student is learning in any other photography class in your school district (or state for that matter). A syllabus is a teacher's way of using that curriculum to make his or her own program work for YOU. Handing work back with grades on them has been spelled out in the syllabus. The principal will back up your teacher on anything that is in the syllabus that you might question. And can you question it? Yes, you can, but you better have some good defensive arguments and evidence that your question is valid.
You have asked a tough question here. As a photography instructor, I know what my students need to learn and how to teach it to almost anyone with regard to different styles of learning. The curriculum gives me direction and my background and knowledge tell me WHAT to teach. The curriculum simply tells me WHEN to teach it. (Kindergarten is different than high school, remember?)
Hope this has helped somewhat. Keep asking questions until you are happy - or at least agree to disagree. You won't be happy ALL the time. By the way, Google Calif. state standards for photography class at high school level. It's all there....