Do Not Speak to Strangers is a valuable lesson for young children about staying safe and cautious around strangers. In a classroom setting, Mrs. Bloom teaches her students, including Barney, key safety rules like not speaking to strangers, even if they seem friendly or offer tempting things. Barney, distracted by his book, doesn't pay attention until he and his friend, Rickie, encounter a stranger offering food and another warning about crocodiles. They remember the lesson, avoid the danger, and learn to trust only those they know. This story encourages kids to stay alert and always follow safety rules when encountering unfamiliar people.