Mary Pope Osborne, AG Ford (illustrator)
Magic Tree House (book 36). This time travel series is a perfect introduction to chapter books for readers age 6 and up. There was a rebranding/renumbering in 2017 and there is now also the Merlin Missions books for more confident readers. In addition, there is a Fact Trackers series. In this story Jack and Annie go to Nepal. The Fact Tracker companion volume is called Snow Leopards and Other Wild Cats.