The intensity builds as puzzles start easy but get harder as you go along. Puzzles will challenge kids (answers are in the back) and get them racing to join those dots. Color them in too! Each of the books in the Challenging...Books series is jam-packed with puzzles that are entertaining and absorbing. Plus, there are time challenges with every puzzle, so kids can try to beat the rest of the best. The only question is...are they up to the test? Encourage them to say yes, and tell them to get ready for hours of stimulating fun!