Grandma was cheated and taken to the police station by her grandson.

This incident highlights the importance of being cautious when receiving suspicious phone calls or messages. In class, teachers have taught students how to "spot" a scam and have even demonstrated ways to avoid falling victim to fraudsters. Students who are able to identify potential scams should report them immediately.

The popular drama series, "Prosecutor," also emphasizes the importance of being vigilant against fraud and provides valuable lessons on how to protect oneself from such scams. Therefore, it is highly recommended that people watch "Prosecutor" to learn more about identifying and avoiding potential scams.

(Note: This summary may not be entirely accurate or complete as it was generated by a non-native Chinese speaker based on the original text provided.)