what AAA class has a school year of 1989-90?
CREATE TABLE "individual_overall" (
  "school_year" text,
  "class_a" text,
  "class_aa" text,
  "class_aaa" text,
  "class_aaaa" text,
  "class_aaaaa" text
);
SELECT "class_aaa" FROM "individual_overall" WHERE "school_year"='1989-90';