All true. I would hope that in a place like California, where tax receipts are remitted to the state and then redistributed, that the leveling I'm talking about would be more prevalent. But perhaps not.
Sure. I'm talking about when the teachers in particular subject and grade levels meet together to coordinate their curricula together so that they are determining TOGETHER what will be taught and how. They create these frameworks themselves and stick to them for a year, then reevaluate. This way, teachers are invested in what they're doing more than when the curriculum is handed to them, but they aren't each completely independent, reporting only to a department chair or principal.
This way, all the teachers can learn from the expertise of each other. They create a situation where students talk to each other about what they are learning, across classes, improving the school as a culture of learning. Sometimes teachers even collaborate across subjects, so student learn different aspects of the same topic in social studies and English, for example.
The key is collaboration between respected professionals rather than the imposition of a curriculum from an outside source.