With the improvement of our living standards, high school students are generally mobile phones or other electronic devices. This situation has caused great problems in school management. Students stay awake at night using cell phones, text messages, and the Internet. During the day, the whole class yawned and the students stooped to sleep. Today, cell phones are used in the classroom so much that students now think they have the right to use them during class. They didn't follow the instructions because they were texting, listening to music on a mobile phone playing a game, or watching a video or movie, so they needed to repeat the instructions multiple times.Using signal jammer in class is easily sovle the hard problem
