Hand-in of mobile phones in party schools refers to handing over electronic devices such as mobile phones to relevant staff when attending party school training or centralized learning activities within the party, so as to ensure the safety and discipline of learning activities. This is because party school training or concentrated learning activities usually need to maintain a focused and serious learning atmosphere to avoid interference and influence the learning effect. Therefore, handing in your mobile phone is a common management measure. Of course, there may be exceptions in some cases, such as when people need to keep communication open in an emergency.