"Do you think that it is important to give extra tutoring to students who are not failing? Can you please explain your answer? Thank you.

Each student should be offered the opportunity to explore the material at her/his own pace and in accordance with her/his own level of interest. A student who is not failing deserves just as much attention as one who is. (The grading scheme only gets in the way of giving each student what s/he needs.)

I think it is important to give students who are not failing extra tutoring but only if the student wants it, because there may be something in some lessons that the student doesn't understand and the student may well be in need of extra help. The student may not want to ask the subject teacher for a number of reasons whether that is because they don't like or get along with that particular teacher or fear of being bullied.