One possible version:

It is well-known that the task of students is to study, so some students regard that marks are very important. They think that their primary task is to study and learn from teachers and textbooks. They seldom take part in other activities, for they are afraid that those activities will affect their study. They put marks in the first place, thus neglecting the development of practical abilities.

However, some other students think it most important to develop one’s own practical ability. They think that students should not only learn the textbook knowledge, what’s more, they should also learn from outside the textbooks. They think one’s own practical ability is of primary importance. So they take the chance to develop their own practical ability seriously.

In my opinion, we should first study hard, but we should not neglect our own practical ability, for when we enter the society, we need various abilities. Without practice, it is hard for us to be useful for the society.