To insure transfer students receive graduation credit for the classes they are taking grades may be stored early. Once a school reaches a point in a term where students have earned credit for the current term, for example a week before term end. This will create the historical grades records that you need. It will also create records for all students. This is okay because they will be overwritten with the updated grades the next time the Store Grades process is ran.
Run the process again on the last day of the term to update the grades and then run the process one final time when all teachers have completed their grading. Do not change grades manually until after the final process or the changes you make may be overwritten. Send an email to firstname.lastname@example.org when you have finalized stored grades so I can fix the NGs and Fs.