What should be done if a child is found in an unusual location?

When a child is found in an unusual location, it is essential to prioritize their safety and locate them effectively. Conducting a grid search starting from the child's last known location allows for a systematic and thorough approach to ensure that the child is safely reunited with their guardians or caregivers. This method increases the chances of finding the child quickly, as it helps to cover the area comprehensively and ensures that all potential locations are searched efficiently.

Looking at the other options, informing the child's parents immediately may not be feasible if the child's safety situation is unclear or if they are in immediate danger. Additionally, leaving the child where they are could pose risks to their safety and well-being, as they may be vulnerable to harm. Taking the child home and waiting for the parents to call does not actively address the immediate concern of the child's unusual location, potentially delaying rescue efforts or placing the child in a more precarious situation. Thus, a grid search is the most appropriate and proactive choice in this scenario.