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The Hardy Boys book cover

The Hardy Boys

The Secret of the Old Mill (Book 3)

by Franklin W. Dixon

Ancient Wisdom Publications 2023

Great fit for 5th grade

Reading level and content both target 4th–8th grade · ages 9–14

5th grade English Fiction
6
AR Points
4.0h
Read time
AR Quiz Available

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Genre

Mystery

Themes

  • teamwork
  • problem-solving
  • courage
  • justice and integrity
  • perseverance
  • family
  • loyalty
  • community

About this book

When a string of counterfeit bills surfaces in Bayport, brothers Frank and Joe Hardy follow a trail of clues that leads to a mysterious old mill on the river. With help from friends and their detective father, the boys use sharp observation and quick thinking to untangle secret messages and suspicious characters. The pace is brisk, the danger is just scary enough, and the puzzles keep readers turning pages. Perfect for middle graders who enjoy classic, clean mysteries with plenty of action and teamwork.

Setting: Bayport and a nearby riverfront old mill, mid-20th-century small-town America

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Frequently Asked Questions

Is The Hardy Boys right for my child?

Yes — The Hardy Boys is a great fit for 5th grade. The reading level is AR 5.3, which is typical for 5th 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 teamwork, problem-solving, courage.

How long does it take to read The Hardy Boys?

At a typical 5th grade reading pace, The Hardy Boys takes around 4.0h to finish. The book has 40,000 words. Slower or faster readers may vary significantly.

Does The Hardy Boys have an AR quiz?

Yes — The Hardy Boys has an AR quiz available, worth 6 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 The Hardy Boys?

The Hardy Boys has an AR reading level of 5.3, which places it at a 5th 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.