Answer:

RETESTS

AnswerCrossword Clue
RETESTSExamines again
RETESTSTries again
RETESTSStudents' second chances
RETESTSChecks again
RETESTSSecond chances in school
RETESTSMakeup exams
RETESTSMake-up exams
RETESTSMakeups for classes
RETESTSMakeups
RETESTSDouble-checks.
RETESTSExamines again.
RETESTSProbes anew.
RETESTSChecks again.
RETESTSTries anew.
RETESTSSecond quizzes.
RETESTSTries over.
RETESTSDoes lab work
RETESTSEvents at school
RETESTSAdditional tryouts
RETESTSExamines anew
RETESTSSome exams
RETESTSChecks to make sure
RETESTSSecond chances for students
RETESTSChecks to make doubly sure
RETESTSDoes a second dry run
RETESTSExamination do-overs