With new computers and a new school year there are two things you can do quickly to save yourself some hassle and some time.  The first is to download Google Drive to your computer so that you can quickly backup your files and have them on your computer as well as in your Drive.  This means that you will not be stuck if you do not have your computer or if your computer all of a sudden does not work.  Also, you should enable it so that your computer locks itself when it goes to sleep or you close your computer screen so that no one else, including students, can get on it and change things.  You would not want any student to be able to just open your computer and read your emails or access the gradebook.