|Weights, Worth, Net, Impact|
Weight, Worth, Net, and Impact on Grade all describe how much an assignment affects the total grade:
Assignment Worth (on the screen) is how many points or grades an assignment is worth. Other gradebooks call these "weighted assignments", since they are like assignment weights within category weights.
When using "points", an assignment is normally worth the same number of points that are possible, e.g., a 10-question quiz worth 10 points. However, you could optionally make a quiz with 10 questions possible be worth 15 points (i.e., each question counts as 1.5 points).
Alternatively on the screen you can change the wording to "grades" instead of "points", e.g., an assignment "worth 1 grade" instead of "worth 1 point". This is just a wording preference; it does not change how grades are calculated. To make all assignments within a category be worth the same, make them each worth 1 grade.
On the screen in Gradebook Mode, you can set how much each objective counts within the assignment. This applies only if "Score objectives separately" is checked. If inputting scores as Points, this is how many points are possible for each objective, which also determines the relative weight. If inputting scores as Percents, Grades or Rubrics, these weights are just relative numbers, so they do not need to add to 100.
On the screen in Admin Mode, you can set how much each objective counts toward the final grade, e.g., set Comprehension to count twice as much as Vocabulary. This is supported only when using Summative grading, not Average grading. These weights are just relative numbers, so they do not need to add to 100.
This is calculated simply as the different between what the current grade is and what the grade would be without that assignment. This is not a chronological history, so a negative impact is what is below the student's current average, which changes whenever you grade more assignments.
Note: The impact is relative to either the cumulative grade (e.g. semester) or the grading period (e.g. quarter), depending if you're using Weighted Grading Periods. This is not necessarily the same grade that is displayed on the Student screen.