Lost City
Tandem Library 1992
Book 5 of The NUMA Files
Great fit for 4th grade
Reading level and content both target 4th–8th grade · ages 9–14
Book 5 in a series — earlier books first
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Genre
Themes
- exploration
- courage
- teamwork
- mystery
- problem-solving
- survival
- perseverance
About this book
A fast-paced middle-grade adventure, Lost City follows a group of kids drawn into the mystery of an ancient ruin hidden deep in the wilderness. As they decode clues and dodge dangers, they learn to trust each other and think on their feet. The story blends archaeology, action, and puzzling riddles that keep readers turning pages. It’s a great pick for kids who love exploration, secrets, and high-stakes teamwork.
Setting: a remote jungle and an ancient underground city
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Frequently Asked Questions
Is Lost City right for my child?
Yes — Lost City is a great fit for 4th grade. The reading level is AR 4.6, which is typical for 4th grade. The interest level is rated Middle Grades (4–8), meaning the themes and content are designed for ages 9–14 (4th–8th grade). Themes include exploration, courage, teamwork. Note: this is book 5 in a series — your child should read the earlier books first.
How long does it take to read Lost City?
At a typical 4th grade reading pace, Lost City takes around 3.3h to finish. The book has 30,000 words. Slower or faster readers may vary significantly.
Does Lost City have an AR quiz?
Yes — Lost City has an AR quiz available, worth 4 points. Your child will need to take and pass the quiz through their school's Accelerated Reader program to earn credit. The quiz is typically 5–20 multiple choice questions about plot, characters, and setting.
What grade level is Lost City?
Lost City has an AR reading level of 4.6, which places it at a 4th grade reading difficulty. The interest level is rated Middle Grades (4–8) — this reflects the age-appropriateness of the content and themes, not just the reading difficulty. A strong younger reader may handle the words fine while the themes are aimed at an older audience, or vice versa.