My top three tips for starting off the school year are location, organization, and tools.
First, have a quiet (as in where you will have few interruptions), well-lit location where you can spread out your work and get comfortable. Perhaps your study ambiance includes background music playing (my son always studies to music; I, on the other hand, like it quiet). Do whatever is going to create the best environment for study.
Second, you must get organized. If your school does not provide a planner, BUY ONE!!! Then USE YOUR PLANNER DAILY!!! Write down daily homework assignments and write on the dates of your planner when long-term assignments are due (use a highlighter for emphasis). If your school uses a block schedule, make the habit of completing your homework assignments on the day they are assigned. If something comes up or you get sick, you will still have a day to finish or to get help. For the long-term assignments, break them up into shorter due dates. For example, for that essay on the First Continental Congress that's due Nov. 1, select a reasonable date to finish the research on the topic, maybe Oct. 15, and then on that date write, "Finish research for 1st Cont Congress essay." Then on Oct. 18, "Complete thesis for 1st Cont Congress Essay/run by 'teacher's name'." Then Oct. 21, "Complete outline 1st Cont Congrs Essay (maybe show teacher)." Then on Oct. 25, "1st draft Cont Cngrs Essay." This gives you time to maybe run it by your teacher and to get peer review. Read it, edit it, read it, edit it etc. to improve paper. On Oct. 30 you should have written, "Finish Cont Cngrs Essay," 'cause no one wants to be writing a paper on Halloween!
Third, gather all your tools and give them a place in your study area. The following should find regular homes in your study area: pencils (regular and colored pencils for pretty drawings of cell contents, etc.), pencil sharpener, pens (black, red, whatever colors your teachers want), highlighters, calculators, index cards (for terms-definitions, Spanish vocab, chem formulas, whatever), calculator, notebook and graph paper (use graph paper for your math assignments - your teacher will be really impressed in how neat you have become! Side note - you can buy spiral bound graph-paper notebooks - use them!). You'll also need binders, notebooks, USB key, paper clips, stapler, and any class specific tools such as protractor, ruler, and compass for Geometry. When you finish using a tool, PUT IT BACK WHERE IT BELONGS so you'll know where to find it when you need it next time. Keep your study area neat. Loose papers can get lost and result in "0s" which will make your parents really mad (I know!) and you could have easily prevented it. Put assignments in folders or binders by subject area. Another important tool is keep a notepad or a Word or Excel document titled Community Service. In that, write down every activity that you take part in that helps other people and that you don't get paid. Include date, description of activity, person in charge or someone that can vouch for you and phone number. Today my son along with a friend helped out for 2 hours at the local elementary school fair for the community. Whether you plan to go to college or not, this info will make you stand out above others who just veg in front of the TV or who play video games all day. Trust me, it will be worth the few minutes to keep a log of your hours and a description of your service activities. It may mean you get the job over the next guy.
Plan ahead, keep track of assignments, stay organized, and always do your best, and you'll do fine. If you find you don't understand something, get help from the teacher and friends. Don't wait!
Good luck and have fun this year!