It's all about the format:
My city's school district makes images of the spreadsheets and then publishes them in a pdf. USELESS
While deplorable from an accessibility standpoint, at least the data is available and out in the open to the public. One small step in the right direction.
EDIT: Tabula[1] is an open source tool to extract tables from PDFs into CSV/Excel format in case one really needs to process data trapped in PDF documents.
Does Tabula do OCR? That's what would be required for tables embedded as images.
> Caveat: Tabula only works on text-based PDFs, not scanned documents. If you can click-and-drag to select text in your table in a PDF viewer (even if the output is disorganized trash), then your PDF is text-based and Tabula should work.