Viking Ships at Sunrise: 15 by Mary Pope Osborne, Sal Murdocca

The #1 bestselling chapter book series of all time celebrates 25 years with new covers and a new, easy-to-use numbering system!

"Beware of Vikings!" warns Morgan. Then Jack and Annie are whisked back to ancient Ireland. They land on a cliff on a misty island. How will they find the story they are looking for? It will take a Viking invasion, the help of a jolly monk, and a lot of courage for Jack and Annie to succeed in Viking Ships at Sunrise.

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 books
Merlin Missions: More challenging adventures for the experienced reader
Super Edition: A longer and more dangerous adventure
Fact Trackers: Nonfiction companions to your favorite Magic Tree House adventures