This is addictive and very challenging at all times. I have never looked at math puzzles before until I struggled with fun on this web sites. I have included my son and husband in trying to solve some of the puzzles I encountered here. My husband and I finally solve the rooster/hen puzzle without knowing that we actually switch sides and wife actually captured the rooster. After that the husband captured the hen. We now have a link on our computer for this math puzzles and actually recommend it to my son to go there and exercise his brain.