It sure is! As difficult as it may be for you to hear this, studying and completing your homework are critical for you as a student. You learn how to organize yourself and manage time — in other words, you're developing personal responsibility and getting yourself ready for your adult life.
Doing homework also helps you develop in other ways. For example, math and science teach you analytical and deductive reasoning (think CSI: Crime Scene Investigation or Sherlock Holmes), while English grammar and composition help you learn to communicate your thoughts and ideas with clarity and expression. With social studies, history, and geography, you get to explore the whole world and understand how other people live.
Think of it this way: Going to school is your job, and you should do your best with all your homework, whether it's reports, worksheets, science projects, posters, word problems, or whatever. Your grades really do count toward your future, whatever that may involve.