Things you may want to avoid doing in the future. 

 Doing, wait, not doing these things always works for me. 

• Staying up late. 
•  Sleep is yes.  And as my speech coach puts it “there are only so many all nighters a person can pull before they just can’t”.  Not only will staying up uber-late make the next day a battle between you an a surprisingly pillow-like desktop, if you’re tired, your work probably won’t be the your best.
• Over-scheduling. 
•  It’s easier to look at a schedule with 3-4 assignments than it is to look at one with 9-10.  When scheduling, if you have a plethora of assignments, prioritize.  Write down the most important assignments, and leave any others off the page or in the margins.  You only have so many hours in the day and it’s better to complete the most important tasks than none at all.

Pro-tip: The Pareto Principle.  The Pareto principle revolves around the 80%-20% ratio.  Allow me to explain, if you have 10 pieces of work, there are probably only two of them that will take up 80% of the work.  And 8 of them that will take up 20% of the work.  The key to prioritizing is finding those two assignments (or however many = 20% in your workload) and doing them first

• Working in bed or laying down.
•  NONONONONONONONONONO.  This is how “cat-naps” happen.  You swear that you’re going to get straight to work and then your phone on the bedside table lights up.  It’s too hard to organize a book, a notebook, and a laptop on a bed without moving the laptop off of your lap.  So why not check it?  

Working in bed helps the boogeyman grow under it.

• Over-working.  
• If you take on more than you can handle, you will not get the results you want.  It’s perfectly alright to challenge yourself.  In fact, it’s great.  But, there is a difference between being ambitious and stressing yourself out.  If it’s too much, go back to the Pareto principle and prioritize. 
• Drinking excessive amounts of coffee and energy drinks. (Especially in the afternoon.)  
• One (maybe two, if you ordered a tall) cups of coffee in the morning is fine.  But in the afternoon or the evening, stick to exercise, healthy snacks, and naps.  Sugary energy drinks as well as coffee that contain caffeine can speed up your heart rate, cause stress, and irregular breathing patterns.  If you become addicted to caffeine these things will accelerate and can end up hurting you detrimentally.
• Over-using productivity apps.  
• Productive apps are awesome, if used correctly, don’t abuse them.  It was difficult for me to use productivity apps on my phone at first because the other things on my phone would distract me.  If you plan to use productivity apps on you phone and computer make sure that you have the self-control needed o use them properly.
• Tumblr. - I’m only half kidding
  

Those are the general ones, these are a bit more subject specific

Math/science

• Falling behind. 
•  In other classes falling behind is not recommended, but is usually fixable by reading a few chapters or asking a friend for notes.  Because of arithmetic’s complex nature that relies not only on facts, but applying them it is very difficult to master one a concept while you’re supposed to be mastering another.  Often, learning one key concept can help you with many other assignments, not learning key concepts can make those other assignments 10x harder.
• Receiving low homework scores.  
• In all of the math classes I’ve been in, the homework scores were more of your grade than your test homework.  Always turn in your homework, even if it feels impossible, try your best, and never leave your paper blank.  Even if you got all of the answers wrong, many teachers will give you serious credit for trying and failing rather than just failing.
• Learn everything from the teacher. 
•  There are a plethora of online math resources that are awesome, and math teachers usually only teach one method of solving a problem.  Try Khan Academy , For Dummies, or IXL.  Or look around a bit, there are a lot of other great sites, those are just my favorites.
• Learn everything. (This is usually for science.) 
•  In science (especially in biology and Earth sciences.) you are introduced to a myriad of concepts and vocabulary words that might seem like too much to memorize.  Don’t.  Look at what your teacher puts emphasis on and memorize that. Also, if you are using a textbook, there is a good chance that the textbook is filled with notes on the ‘key concepts’ or learning requirements for each chapter.  These are also things that you should attempt to memorize.

English/writing/history/ other humanities

• Not develop an opinion. (Especially in history) 
•  If there’s anything a english/ writing/ history teacher loves, it’s an opinionated student.  Textbooks give you facts and figures, and you can interpret them however you want.  So, do just that.  This will show your teacher not only that you are interested in his or her subject, but that you are engaged in the material that they gave you.
• Ignore teacher comments. (No matter how small.) 
•  It isn’t fun to read nit-picky comments about your work.  Especially on your writing.  But look at them.  Even if you receive a good grade on a paper, applying corrections on your next one will ensure that you get a better grade the next time.  
• Staying quiet in class.  
• I understand that for some people this one is hard, for some people this one is practically impossible.  But teachers love it.  If you can, voice your opinion and answer questions in class as frequently as possible.  I’ve even received extra credit for being verbally engaged in class more than other students.
• Not trying to learn everything.  
• This one is a lot like the ‘not ignoring teacher comments’.  A lot of information slips through the cracks (especially in english)  that pops back up on exams.  Because most of what is learned in an english class is not drilled into you like it would be in a math or science class, to do well, you have to drill yourself.  I’ve been told the difference between ‘affect’ and ‘effect’ plenty of times, but I didn’t truly learn it until this year when I had to study it for an exam.

Pro-tip: Don’t challenge your teachers.  They determine your grades.  Momentary satisfaction is not worth a bad grade.

Hope this was useful!