The Other Merlin Series by Robyn Schneider
Blurb - Prince Arthur's a depressed botanist who would rather marry a library than a princess, Lancelot's been demoted to castle guard after a terrible lie, and Emry Merlin has arrived at the castle disguised as her twin brother since girls can't practice magic.
Announcement- This is going to be a trilogy but only two books have come out now. The third will be out in 27th August and will be called: The New Camelot.
Book one : The other Merlin: I rated was a 5*
Book two : The Future King : I rated was a 3*
My non spoiler review : I love retellings and this for me is one of the best I have read so far. It had a new take on King Arthur and his story. It was a light hearted and entertaining it really gets interesting as it goes along. I love the character development and it really felt as though, when you were reading, it played out as a movie in your head. Overall it is defiantly worth a read if you are struggling to find a good series this is the one for you.