SELECT DISTINCT T1.lastname FROM list AS T1 JOIN teachers AS T2 ON T1.classroom = T2.classroom WHERE T1.grade = 3 AND T2.firstname <> "COVIN" AND T2.lastname <> "JEROME"
Which students in third grade are not taught by teacher COVIN JEROME? Give me the last names of the students.
CREATE TABLE teachers (
    lastname text,
    firstname text,
    classroom number
)

CREATE TABLE list (
    lastname text,
    firstname text,
    grade number,
    classroom number
)