CREATE TABLE table_66013 ("School" CLOB, "Location" CLOB, "Mascot" CLOB, "County" CLOB, "Year Joined" CLOB, "Year Left" CLOB)

Which year did the school with the mascot of the Vikings join?
SELECT "Year Joined" FROM table_66013 WHERE "Mascot" = 'vikings'
SELECT "Year Joined" FROM "table_66013" WHERE "Mascot" = 'vikings'