FWIW, our district has made some changes up through Algebra II as we align with common core (or at least I assume the changes were due to our district's decision to adopt common core - it's a little weird in that there was a lot of publicity about common core when the decision was made a few years ago, but the way the post-adopt-common-core math curriculum changes were explained doesn't refer to common core, just to a "recent change" in curriculum specs
This type of obfuscation is not uncommon, however it IS possible to know what has shifted in your district's curriculum. Public (government run) schools in the United States are subject to transparency laws sometimes called sunshine laws, which require open records to be shared upon request. Specifically, a parent or taxpayer can request to see the alignment documents. These will show what was added, deleted, changed, moved up one or more grades, moved down one or more grades.
