It’s an annual back-to-school routine.One morning you wave good-bye,and that 　21　evening you"re burning the mid-night oil in sympathy.In the race to improve educational standards,　22　are throwing the books at kids.　23　elementary school students are complaining of homework fatigue.What"s a well-meaning parent to do?
　　As hard as　24　may be,sit back and chill,experts advise.Though you"ve got to get them to do it,　25　helping too much,or even examining answers too carefully,you may keep them　26　doing it by themselves."I wouldn"t advise a parent to check every　27　assignment,"says psychologist John Rosemond,author of Ending the Tough Homework,"There"s a　28　of appreciation for trial and error.Let your children　29　the grade they deserve."
　　Many experts believe parents should gently look over the work of younger children and ask them to rethink their　30　.But"you don"t want them to feel it has to be　31　,"she says.
　　That"s not to say parents should　32　homework-first,they should monitor how much homework their kids have.Thirty minutes a day in the early elementary years and an hour in　33　four,five,and six is standard,says Rosemond.For junior-high students it should be"　34　more than a hour and a half," and two for high school students.If your child consistently has more homework than this you may want to check　35　other parents and then talk to the teacher about reducing assignments.
____.

A. teachers

B. parents

C. professor

D. schools