How to whiten your teeth? something that really works?

what really works? and something that is not too expensive, i am still in highschool i cant spend that much mother wont let me.
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You could try Listerine Whitening Mouthwash. I use it everyday and it makes my teeth whiter. It only costs about $3-6 but there is also a generic brand which are usually a little cheaper. Just use it before you brush your teeth in the morning and at night. You can tell the difference in the shade of your teeth in a couple of days.
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