When a boy hits puberty his body begins releasing a horm-
one called testosterone which causes changes in the body, including the larnyx which is also known as the voice box. The larynx matures which then leads to his voice changing. Once again this is just a normal part of the body growing up. The hormones in puberty will cause the male vocal cords to get thicker and longer. One day, the high-pitched voice will suddenly crack. This will eventually stop. When it does the voice will be deeper and it will stay that way. Your voice won't change though until you are almost done with puberty.Sources Webmd and KidsHealth.com
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