"Top Secret" curriculum at BCPS?

Can someone explain to me why public school administrators talk incessantly about "the curriculum", but seem determined to ensure that parents don't get to see it?

The mission of the Baltimore County Public Schools' Department of Curriculum & Instruction includes this bit:

development of curricula, based on research and best practices, provides teachers, students, and parents with a quality instructional program

But the BCPS website hides nearly all details of the curriculum behind a password-protected intranet.

All we parents get to see on the website is fluff, peripheral material, and educational mumbo jumbo about "seeds", "clarifications", "sample assessments", "thinking skills", "Articulated Instruction Modules", "Core Learning Goals toolkits", "parent summaries" that don't exist yet, and so on. And this comes in an Alice-in-Wonderland format that is impossible to skim in an efficient way.

UPDATE: Joanne Jacobs links, and asks her readers, "Do other school districts make it hard for parents to access the curriculum?" Thanks Joanne. The comments she gets are enlightening. Another thing I'd like to know: which largeish school systems out there (1) have an excellent curriculum, and (2) make the curriculum easily accessible on the web?