I wanted to go to a high school where there wouldn't be many other Japanese students.
I wanted to go to a high school where I would be much less likely to see other Japanese students.
ーI wanted to go to a high school where there wouldn't be many other Japanese students.
「他にたくさん日本人生徒がいない高校に行きたかった」
a high school where there wouldn't be many other Japanese students で「他にたくさん日本人生徒がいない高校」
ーI wanted to go to a high school where I would be much less likely to see other Japanese students.
「他の日本人生徒をほとんど見かけない高校に行きたかった」
a high school where I would be much less likely to see other Japanese students で「他の日本人生徒をほとんど見かけない高校」
ご参考まで!
I wanted to go to a high school with relatively few Japanese students.
「日本人が他の学校より比較的少ない高校が良かったから」という理由を伝える場合は、
I wanted to go to a high school with relatively few Japanese students.
と表現できます。
relatively は「比較的」という単語で、few は「(数が)少ない」という意味です。
relatively few とすることで「比較的少ない」というニュアンスをうまく伝えられます。