Alex,
The labor force/educational attainment variables/data are only meant for mapping purposes due to that they are not available at the block group level (only census tracts and large geographies). Unfortunately they do appear in products like the BAO reports add-in and in Business Analyst Desktop that they can be used like a standard variable which will cause the operation to fail.
On the better news front when the 2013 ACS dataset is released later this fall labor force/education attainment variables will be available at all geographies and will be integrated into various reports and in tools like create custom comparison reports in BAO or in the Append Data tool in Business Analyst desktop.
Regards,
Jason R.