If it is becoming common everyday then do the following:There will be some periods like PT,library etc which is not done in the class.At that time some time before the period starts,keep some money in the desk of the teacher and keep in mind that everyone has seen you keeping money there.Then when all the students will move out of the class you should hide somewhere in the class or outside the class,so that you can see the class clearly.If that person who steals everybody's money has saw you keeping money there then he will surely come there to take it and thus you can catch him and report it to the class teacher or to the concerned authority. hope I helped u.. Plz mark as the BRAINLIEST answer..
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Make a mark on your note (write your name).Then after you have lost your money check everybody's note.On whichever note you find your name then you can point out the person as thief.
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