For students time management is important because students have a lot of tasks to do in their daily life. They have to attend schools / collages, tution classes, have to study, complete projects and homework, etc. This all tasks make the requirement of time management skill. Many of the students are unable to do all these tasks. They rather lack in something or the other because they don't have a proper time management skill. A proper time management skill is important for :

Academic Success : If you can manage your time, you will get more time to study and thus your academic scores will increase.
Reduce Stress : Every students have responsibilities to complete. If you manage your time properly you can complete all your tasks, which will reduce your stress.
Goal Achievement : Time management helps students to break down their larger goals into smaller tasks and make students more organized.
Increase Efficiency : Time management skill will help students to increase their overall potential and efficiency ( Your speed of completing tasks ) of completing tasks like homework, preparation for test.
Preparation For Future : Developing a strong time management skill will help you in your future because nowadays, time management skill is a essential requirement in every career or sector of work.
Enhance Work – Life Balance : It is important to take care of your health and remove time for relaxation, hobbies, time pass, friends, games ( indoor or outdoor ) and other activities.
Students have many benefits by improving their time management skill. You must have heard from someone or from somewhere that making a time table is the first key to success. Your time management skills will also help you to achieve your first key to success. Remember, you have to make time table which you can follow easily and not a time table which have every task , you don't like to do. Thus, time management skill is important for students as well.