This series is an absolute keeper. We used this as the first "Chapter Book" for reading to our kids over multiple nights when they were 4. They also are reading it to themselves.
The stories provide a great education on a broad set of topics throughout history in a very entertaining setting. Loved it.
The Magic Treehouse series is a fun "read to" for early readers. The series has been very popular with our first grader for a snuggle bedtime story. The adventures of Jack and Annie are fun to follow, sentence structure is easy and some cultural education is woven into each story.
My daughter started the Magic Treehouse book series when she was 4 (she's 5 now.) She loves the stories and we end up reading whole books in just a couple of nights. (The website is great, too - You can print out your Magic Treehouse Passport and earn "stamps" as you "travel" from place to place via the books by answering multiple choice questions about the books. ) I think this series is a great series to choose for kids just starting out with chapter books.
This book and the whole series are great for beginning readers. They really helped my child enjoy reading because the words are short and simple, while the story is exciting and compelling. The author usually throws in a long word or two that she explains the meaning of. Each book has a bit of history from somewhere in the world.