According to this Starbase UGC blog post (and subsequent comments), Starfleet Academy was at one stage available as a Foundry map, but as of July 2011, is no longer an option.

I joined STO fairly recently this February, and despite not being able to use the Academy map myself, I've seen relatively newer Foundry missions that make use of the Academy.

When can I expect the map to be available in the Foundry again? Could I try asking someone with a mission that makes use of the Academy to allow me to import their project so that I can have access to the map?