grade_school has definitions from the field of education
1
[ noun ] (education) a school for young children; usually the first 6 or 8 grades

Used in print

(Tristram P. Coffin, "Folklore in the American Twentieth...)

Publishers want books that will sell , recording_studios want discs that will not seem strange to ears used_to hillbilly and jazz music , grade and high_schools want quaint , but moral , material .

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