Many of the students who don't do well academically are also the students who are disorganized. While keeping things neat and orderly may come naturally to some, for others, it's a skill that needs to be taught.
Supplies. Make sure you start the year with all of the supplies your teachers recommend. Making one trip to the store is a lot easier than having to run back for odds and ends later. Keep lots of extra pencils in your locker, as they have a tendency to get lost easily.
Lockers. Don’t be tempted to use your locker as a catch all or even worse, as a trash can. At the end of each day, take home any trash, clothing, unneeded items, or other things that are just getting in the way. Keeping your locker clutter-free will help keep important things from getting lost. Use magnets to post important reminders or to do lists on the inside of the door. You can even buy magnetic pencils holders, clips, and other supplies to help keep small items in view. Find a home for your backpack, binders, textbooks, supplies, lunch, and jacket, and then return each item to that same spot each time. Knowing where things are will save you time and stress during the few minutes you have between classes.
Binders and notebooks. Use dividers to keep your binder organized. Often teachers will require you to have certain sections: otherwise, make common sense divisions (notes, returned homework, homework to be handed in, returned tests, etc.) Keeping things together helps you find them quickly. Most importantly, file each piece of paper in the proper section immediately. Don’t be tempted to shove things in randomly without clipping, or to “temporarily” put things in the pockets to organize later. These types of “to do” piles have a tendency to grow quickly, and you may be tempted to procrastinate about sorting a huge pile. It’s much easier to file each piece as you get it. Keep lots of extra paper on hand in each binder, and until you have it memorized, it’s probably a good idea to keep a copy of your schedule in the front of each binder as well.
Assignment book. Don’t plan to rely on writing assignments on random scraps of paper. They always get lost, and it’s much easier to have everything in one centralized location. You can simply use a small notebook, but a better idea is probably a structured assignment book. These are usually dated and have space devoted to each subject. Get in the habit of copying your assignments down as soon as you get into class or as soon as the assignment is given. Refer to the assignment book as you’re packing up to leave to make sure you have everything you need to complete your homework. Also refer to it while doing your homework; it’s a mistake to rely solely on your memory. Check things off as they’re complete. Most importantly, put your finished assignments back in a place you can easily find them when you’re ready to hand them in. Don’t just shove them into your backpack. A good idea is to have a section for completed work in your binder (as mentioned above), most practically, this would be the first section so it’s right there when you open your binder.
For further information on how to support your child's academic efforts, you may also be interested in Top Stresses for Middle Schoolers or Surviving Middle School.