Because male high school students are boys and female high school students are girls. This remains the case until such time as an individual reaches the Age of Majority, which is 18. Afterward, they are legal adults, and thus entitled to being called "men" and "women".
"Almost 18" doesn't count.
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No love for Hamas, Hezbollah, Iranian Leadership, Islamic Jihad, other Islamic terrorist groups, OR their supporters and sympathizers.