Which of These Things Do Not Belong?

I am teaching my ninth graders The Odyssey.  To introduce the mythology unit, we are watching The Lightning Thief.  It is also a good jumping on point to introduce The Olympian books for free read.  I was so proud of my students for their observation of Persephone.

In the movie, Rosario Dawson plays a slutty and disenchanted Persephone who hates her Hades abode.  She makes reference to the fact that she has time above ground that she looks forward to.

My students, though, remember me telling them that she lives in Hades during winter and one student pointed out that the movie takes place in the summer (the week of June 21st to be exact).  I was so proud!  I'm sharing it with you since many teachers read this and it could be a fun quiz question or extra credit question.

Now, to be fair to Rick Riordin, he gets it right.  In the book, Persephone is no where to be seen.  What you do get in the book that is absent from the movie is the wonderful scene of Percy trying to get past Cerberus by playing fetch with him using a nice red bouncy ball.

I'm not sure why Chris Columbus chose to drop Cerberus and use Persephone instead.  I don't think it added to the movie any and all it does it irritate myth nerds like myself.  I don't know if Riordin had any veto power over the movie script or not.  I do know that he never has watched the movie.  Why?  He says that he never watches movies based on books he's read as he likes the picture in his mind better.