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Well.. the US in not any better. Sex for me was a chapter in Bio 2 (11th Grade) and a section in P.E. (9th grade) not much info given in them either. Given that the first Couple in my grade happen in 3rd grade and we got no formal info till 9 th... lol Glad I had my mom who explained thing as they were and understood the posible trouble of me not knowing.
And yes sex ed is lacking all arong the world cause not many contries that I know of have a you have to teach them this by then list for it.
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I'm from Europe and sex ed is the worst ;) In junior high our teachers were showing us homophobic movies about "how to cure homosexuality". Or my male teacher on every class needed to remind us (girls group) that woman are supposed to be good little housviwes... No talking about anatomy and protection so everyone looks for information in web. And yeah i guess effects are obvious
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in the school i am in we only got taught how babies were made and that was it. we weren't taught how to have sex or what it was. we only had one lesson on it as well. this was in year 7 and the subject was never touched on again. the rest i had to find out from my parents, it was a super awkward conversation. i swear i died of embarrassment.
Is there no sex ed at all in japan??? This isnt a first of a high schooler not knowing things that happen to their own body...