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A noise alarm that reacts only when the whole child is not responding to the teacher's voice

Activity class or debate If you take a class, your activity will become louder and louder, as it will interfere with the lesson class. You have to give the surroundings to keep quiet.

So, even if you do not have to intervene, you will automatically detect the loud noise and make it work.

If you adjust the activity time in class and press play button, the alarm will be activated.

You can adjust the alarm level to determine how much the alarm will sound

By adjusting the sensitivity, you can stop responding to your voice.

Refer to the link below for further explanation. Http://sciencelove.com/1493