Таблица schools

CREATE TABLE schools 

(id INT

 , grade_1_cnt INT

 , grade_2_cnt INT);

INSERT INTO schools (id,grade_1_cnt,grade_2_cnt) VALUES (1,10,11);

INSERT INTO schools (id,grade_1_cnt,grade_2_cnt) VALUES (2,21,22);

INSERT INTO schools (id,grade_1_cnt,grade_2_cnt) VALUES (3,33,34);