Challenge Series

Fun questions across a range of subjects get you thinking about what you know (and don’t know) about the world around you. Challenge yourself and friends with these probing questions that will expand your knowledge of the world around you.

The Challenge Series app has 1520 challenging problems in sixteen books in four different subject areas for kids to explore:

GEOGRAPHY CHALLENGE volumes 1-4
HISTORY CHALLENGE volumes 1-4
MATH CHALLENGE volumes 1-4
SCIENCE CHALLENGE volumes 1-4

In each subject area, there are four volumes of question banks: volumes 1 and 2 are easier and volumes 3 and 4 are harder. Each book presents 95 cartoon-illustrated word problems with answers available just a tap away.

The first 10 questions in each book are free with the remaining 85 questions available as in-app purchase: an individual book, the subject series (four books; 10% discount), or the entire Challenge Series (all 16 books; 20% discount).

About ReadSmart
ReadSmart is a set of patented technologies created by Language Technologies, Inc. for improving reading comprehension, speed, and enjoyment and is used in a variety of publishing fields. ReadSmart's algorithms analyze text to give document-specific results: the arrangement of text for a document is optimized while preserving the designer’s layout. Once a digital book has been created using ReadSmart technology, nothing is lost and it retains the look and feel of the printed edition, not a generic electronic document.