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coeducation
この学校は創立当初から共学だったそうだ。
I heard this school has been coeducational since its founding.
共学に移行してから校風が大きく変わった。
The school culture changed significantly after becoming coed.
最近は共学の学校を選ぶ家庭が増えている。
Recently, more families are choosing coeducational schools.