Class    Exam    Grade
Math1    Mid       1
Math2    Mid       2
Math1    Final     1

SELECT *
FROM table
WHERE Class = 'Math1'

SELECT view1.*
FROM
 (SELECT *
  FROM table
  WHERE Class = 'Math1') AS view1, view2
WHERE view1.Exam = view2.Exam
AND  view1.Grade > view2.Grade