The #1 bestselling chapter book series of all time celebrates 25 years with new covers and a new, easy-to-use numbering system!Camelot is in trouble! Jack and Annie must find four different kinds of writing that will help. Their quest leads them to the American Revolution, the American Civil War, the stormy Great Plains, and the great San Francisco earthquake. It's a difficult and dangerous mission, but Jack and Annie will do anything to save Camelot!Books in this set include: Civil War on Sunday (#21), Revolutionary War on Wednesday (#22), Twister on Tuesday (#23), and Earthquake in the Early Morning (#24).Did you know that there's a Magic Tree House book for every kid?Magic Tree House: Adventures with Jack and Annie, perfect for readers who are just beginning chapter booksMerlin Missions: More challenging adventures for the experienced readerSuper Edition: A longer and more dangerous adventureFact Trackers: Nonfiction companions to your favorite Magic Tree House adventuresHave more fun with Jack and Annie at MagicTreeHouse.com!