The National SAFEKIDS Campaign recommends that no child under the age of 12 be left at home alone. However, consider a child's age and maturity level. For example, if a child is extremely impulsive, it might be best to wait until he or she is older than 12.
Did people and dinosaurs live at the same time? No! After the dinosaurs died out, nearly 65 million years passed before people appeared on Earth. However, small mammals (including shrew-sized primates) were alive at the time of the dinosaurs.
No, people did not exist during the time when dinosaurs roamed the earth. The dinosaurs all went extinct about 65 million years ago (thats a long time!). The current thought, based on fossilized remains and archeological evidence, is that humans did not exist until about 2.5 million years ago.