Jack and Annie lead a perfectly normal life. Perfectly normal, that is, until they come across an abandoned tree house with the power to whisk the kids away to different times and places! Whether they're exploring the ancient pyramids of Egypt-and helping out the ghost of an Egyptian queen-or crossing the Delaware with General George Washington, Jack and Annie are always ready for another adventure. More importantly, the facts they learn along the way always provide the keys to completing their quests. The siblings love to read up on any subject-whether it's to crack codes, solve riddles, or simply get out of scrapes. And as readers follow along on each magical journey, they are introduced to all kinds of interesting information about different time periods, key historical figures, and various cultures and civilizations. With plenty of facts mixed in with tons of excitement, each book provides a great foundation of knowledge that supports future learning.