Tuesdays at the Castle - by Jessica Day George

Castle Glower is not your ordinary castle, and Celie is not your ordinary princess!  This 11-year-old has the interesting habit of mapping the castle, which is made all the more difficult by the fact that each Tuesday, the magical castle changes its layout! A new hallway here, new rooms there, you never know what a Tuesday will bring.

One fateful Tuesday brings more than changes: When Celie's brother graduates from Wizard College and her parents go to his graduation, a number of foreign visitors come to the castle, and they are NOT just there to pay their respects.  Before long, Celie has turned from the youngest sibling who nobody takes seriously into the only person who can save the castle and her brothers and sisters from their enemies.

This is a fast-paced, creative, magical, exciting story of adventure and courage.  What seems at first to be a silly magical princess story for young girls is ACTUALLY a rollicking adventure novel for readers of all ages.  The writing is excellent, the characters and setting intriguing, and the plot rolls out perfectly.  With a non-speaking magical castle as a main character, this is not your typical story, but it is unusually good, and I plan to read the entire series.