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Do you need to improve your grades in only one class, or many? Do you have assignments left to be submitted, or only the final exam? Make a list of all the classes you currently have, what needs to be done for each class, and the due dates for all assignments and exams. In order to get the "big picture," use a calendar to mark out all your assignment due dates and exam dates. Sit down and think about how you've been studying up until this point. Analyze what has worked and what hasn't - then ask yourself why. Make a list of things you want to avoid doing in the future (e.g., procrastination) - and don't do them. Figure out what your motivations for studying are and take advantage of them. This is a good opportunity to learn how to do a S.W.O.T. (Strengths Weaknesses Opportunities Threats) analysis. The SWOT analysis method was designed for businesses, but can easily be adapted to your personal academic situation. Ask your teacher(s) for advice on how you can improve, and where you might have gone wrong. Keep in mind that this conversation could go one of several ways. If you've been a lazy student up until this point, and you're now asking for help, some teachers are not going to be impressed. Make sure you approach them sincerely and then actually follow through on their advice. If you ask for their help and then don't follow it, they're probably not going to be too thrilled to help you again in the future. Ask your teacher if there are any assignments you can do for extra credit. Ask your teacher if you can hand-in any outstanding assignments, even those past the deadline. Or if you can re-do any assignments you did badly on. Ask for help as soon as you know you're having trouble. Do not wait until the last minute to ask for help, or to ask for things such as extra credit. In most cases it will be too late for you. Your parents don't want you to get bad grades, and if you admit you're having problems, they will likely want to help. Even if all you need them to do is constantly follow-up with you to make sure you're doing your work, asking for help is a good idea. Keep in mind that showing this initiative to your parents may help them provide additional support to you in the future. For example, if they see you're having a lot of trouble with math, they may be able to hire a math tutor to work with you the next semester or during the summer. Look through your calendar of things you still have to do and make a detailed schedule. Assign specific study goals to yourself everyday, and the times each day that you'll spend on studying. Try not to schedule large amounts of time for one topic unless absolutely necessary. Try to study more than one topic per day if possible. Remember that smaller chunks of daily study time are more effective than a huge cram session or two. If you're in college, you should plan to study 2-3 hours per week for each credit hour you're enrolled. So, if you're in a 3-hour history class, you should plan on studying an additional 6-9 hours per week for that class. If that sounds like a lot, that's because it is -- and it's what it usually takes to get good grades. Don't forget to reward yourself for meeting your goals. These rewards just need to be small things to keep you motivated to move forward day-by-day - such as allowing yourself an hour to watch your favourite TV show, or an hour to play a video game. Save the big rewards for when the semester is done! While not the best advice, if you are down to the wire, cram. Stuff in as much as you can, in whatever time you have left. Drink lots of caffeinated beverages. Forego (some) sleep. Consider this your "hail mary" play and do the best you can. Avoid getting distracted during cram sessions. Turn off your phone and the TV. Don't listen to music with lyrics. You have very limited time, so use it wisely. This is, of course, assuming this wasn't the last semester of school you're ever going to take! If school is not over, take this opportunity to get yourself ready for the next year or semester. Buy yourself an academic calendar or organizer. Review your course syllabi before classes begin. Make sure you have all the materials you need for each course before the start of the semester, if possible. Organize your study space. Research the various ways of getting academic support on your campus (i.e. success centres, writing centres, tutors, etc.). No one likes going to class in the summer, but if you're looking to improve your grades this is definitely an option. You may want to consider re-taking a class over the summer (to increase your grade) or taking a supplemental class to help you prepare for a hard class you have coming up. At the post-secondary level there are additional benefits to taking one or more classes in the summer term: you can reduce your workload in the fall and winter terms, or reduce the total amount of time you spend in college; some summer programs are offered in other countries or at other colleges, giving you a chance to travel; if you're aiming to take a specific course with a prerequisite, you can get the pre-req out of the way early.
Calculate where you are in the semester and what you have left to do. Assess your current studying techniques thoroughly. Talk to your teacher. Talk to your parents. Create a study schedule and get yourself organized. Buckle down and stay buckled down till it's over. Make plans for the next school semester or year. Go to summer school.