The Number Devil

Common Sense Media says

Unique math title covers unconventional concepts.





What parents need to know

Positive messages

The Number Devil is a little mouthy--but it works for his character.

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Drinking, drugs, & smoking
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Parents Need to Know

Parents need to know that the interaction between Robert and the Number Devil can be edgy at times. The math content varies in difficulty, making it an uncomfortable fit for some children because some of the math may be too hard or too easy.

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Kids say

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What's it about?

THE NUMBER DEVIL presents a mathematical adventure that explores concepts such as infinite numbers, prime numbers, fractions, decimals, powers, and square roots. Robert, a boy who thinks \"mathematics is child abuse,\" narrates the story. His opinion of math changes after he's visited in his dreams for 10 nights by the Number Devil, a mouthy but charismatic character.

The Number Devil introduces math concepts in clever and unusual ways: For example, to explain permutations, the Number Devil shifts Robert's whining classmates around to show the different possibilities. Players end each night by exploring a related math game. Following the permutations lesson, the game is to construct a racetrack by using four-color cubes placed in four possible positions and then racing a car.

Is it any good?


Some of the games are better than others, and a few have difficult controls. But overall, kid-testers found the games to be interesting and fun to play. The combination of Robert's pluck and the Number Devil's edgy demeanor creates an engaging dynamic.

However, the math content varies in difficulty, making it an uncomfortable fit for some children. It's too difficult for kids struggling with math, even though the presentation is novel and jazzy. And for math whizzes, the content may seem like cotton candy -- sweet at the beginning, but unfulfilling at the end. However, for kids who think math is boring, here's a chance to put some fun and creativity back into a topic that is far from linear.

Families can talk about...

  • Families can talk about real-life applications for the math concepts covered in the game. Is it easier to learn math through games? Why or why not?

Game details

Platforms:Windows, Mac
Available online?Not available online
Release date:September 25, 2004
ESRB rating:E for (Mac, Windows)

This review of The Number Devil was written by

About our rating system

  • ON: Content is age-appropriate for kids this age.
  • PAUSE: Know your child; some content may not be right for some kids.
  • OFF: Not age-appropriate for kids this age.
  • NOT FOR KIDS: Not appropriate for kids of any age.

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Our star rating assesses the media's overall quality.

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Learning ratings

  • Best: Really engaging; great learning approach.
  • Very Good: Engaging; good learning approach.
  • Good: Pretty engaging; good learning approach.
  • Fair: Somewhat engaging; OK learning approach.
  • Not for Learning: Not recommended for learning.
  • Not for Kids: Not age-appropriate for kids; not recommended for learning.

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Teen, 14 years old Written byturtlekins February 9, 2010


I learned more from this book than i would ten years in the school system. it's a little confusing for younger kids, but its a great book. Definitly read it!
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