School District: We Didn't Know Sasha Grey Was So Anal

The school district that first denied to TMZ they allowed a hardcore porn star to read to first graders has now changed its tune, acknowledging she did indeed make an appearance, but they thought she was a mainstream actress -- not the winner of AVN's 2010 award for "Best Anal Sex Scene."

After the the Compton Unified School District told us Sasha Grey never read to students, we posted this pic which clearly shows otherwise.

Now District officials tell TMZ ... an outside talent coordinator informed the school Grey's calling card was an appearance on "Entourage."

The District says they will now shore up their procedures to make sure "controversial figures" are persona non grata.

Another happy ending ...