Riddles for children should challenge their thinking without being too frustrating, such as the following: "What has a face and hands but no arms or legs?" The answer is a clock, which has a "face" with numbers and "hands" that indicate time.
Another riddle that promotes similar thinking is the following: "What has a neck but no head?" The answer is a bottle, which has a neck and a top but no head.
Some riddles are a little more challenging, as in the following: "Poor people have it, and rich people need it. If you eat it, you die. What is it?" The answer is "nothing." Poor people have nothing. Rich people have everything, so they need nothing. And eating nothing makes a person starve to death. A similar riddle is the following: "I'm tall when I'm young but short when I'm old. What am I?" The answer is "a candle," which gets shorter as it burns down.
Some riddles play on words, as in the following: "What is black and white and red all over?" The answer is "a newspaper," which is white paper with black writing. The play is on the word "red," or "read" in this case. A similar play on words comes in the following riddle: "Why can't a woman living in Canada be buried in the United States?" The answer stems on the word "living," because a living woman doesn't get buried.