Surprise best seller
A book that teaches kids how to climb trees and make catapults has become a surprise best seller.
The Dangerous Book For Boys is in the top five of a big online bookseller, and is full of tips on old-fashioned pursuits and true adventure stories.
There are chapters on conkers, pirates, dinosaurs, coin tricks ,how to build a treehouse, capturing spiders ,writing in invisible ink and marbles.
It takes a relaxed view on safety, saying: "Accidents are going to happen. You can't spend your life worrying about them, or you'd get nothing done."
Brothers Conn and Hal Iggulden who wrote the book said it was all about the sort of things they'd been interested in when they were kids.
"You can't stop boys being curious so they might as well have the tools and instructions to focus that curiosity. In the long run it's a lot safer than having them grow fat and irritable in front of the TV," they said.