I have my grades set up in 3 categories where the lowest lab and classroom grades are both dropped (no test grades are dropped).

I would like to know if doing so could potentially lower a students grade? For instance the student has an overall average of 76 (due to test scores), but the lowest lab and classroom grades could potentially be 9/10 or 10/10.

Or is there a provision that prevents dropping allow grade from lowering the overall grade.

Wesley Allen Gwaltney,

I'll start with the last question. The answer is no, there is no provision that keeps dropping a grade from lowering the overall grade. The dropping of a group is made at the assignment group level and each group is handled independently and separately of the others. Then the values for each group are returned and the average for the entire course is calculated. There is no comparison of dropping vs not dropping as it relates to the final course grade. I just looked at the source code of the part that calculates which assignments to drop to verify this.

Now a different question. Are you using weighted assignment groups or just points?

If you're using weighted assignment groups, then no, dropping the lowest grade in homework and labs will not cause you to lower the overall grade. I could do a mathematical proof of that, but it's probably not necessary. You can stop reading this response (even though I think it's quite informative).

However, if you are dropping lowest grades and using straight points without assignment groups weights, then yes, dropping the lowest grades in some categories could lower the overall average.

Let's say that you had 5 homework assignments, 5 labs, and 3 tests, worth 10, 10, and 100 points each respectively. That makes 400 points possible in the semester.

A student with a 76% would have 304 out of those 400 points.

If the lowest grade for homework and labs was both 9/10 points, then when they were dropped the student would now have 286 points out of 380 points, which is a 75.26%

Here's a quick spreadsheet to show that in more detail. The Before and After columns refer to before dropping and after dropping

You asked about a provision that Canvas had for not making sure the grade goes down. The answer is still no, but I've got a couple of suggestions.

The first approach is one that other people in the Community are likely to give and I'm telling you that you will most likely be able to ignore it. The most common suggestion is to not drop the lowest grade automatically using a grading rule, but to the manually go in and excuse (EX) the lowest homework and lab grades for everyone who would do better but not for those who would do worse. That is a lot of unnecessary work for most people.

Most people who are using straight points are using the functional equivalent of a weighted gradebook without realizing it.

For example, in the example I've given, I've got 50 points of homework, 50 points of lab, and 300 points of tests. That means that I've got 50/400=12.5% in homework, 50/400=12.5% in labs, and 300/400=75% in tests. I could easily go in and use a weighted gradebook with those weights and keep the gradebook exactly the way I have it right now.have the same effect that I have without them.

Here's the same information as above but using a weighted gradebook. The possible represents the possible points in that assignment group and the score represents the total for the student before dropping the lowest grade. The Before and After columns represent, as before, the percentages in each category before and after dropping the lowest grade (the 9 out of 10 for both homework and lab).

The percentages before you drop are exactly the same as what it was with an unweighted (just points) gradebook. But now that you've dropped the lowest grade, the overall grade goes up, not down.

Now it is possible that you really intended that there would be 4 homework and 4 labs counted in the final grade, so instead of having 50+50+300=400 points possible, you have 40+40+300=380 points possible. Homework is now 40/380=10.52631579%, labs are now 40/380=10.52631579%, and tests are now 300/380=78.94736842% of the grade. However, this messes up the 76% now that exams are weighted more and so that student with a 76% overall would have a lower grade of 75.26% if you weighted it based off the 380 possible points instead of the original 400 points. If you note, that 75.26% is the same as what it would have been with an unweighted gradebook and dropping the lowest homework and lab score.

I got the sense that's what you trying to avoid, but if that's the way you intended the grade to be calculated, then you should not switch to a weighted gradebook, just keep the points, and drop the lowest grade and let the grades go down. It wouldn't have mattered if it was on paper and pencil or not. You're not going to give some people 50 points of homework and 50 points of lab when the syllabus called for 40 of each, so don't do it in Canvas, either. Those students who are hurt should have done better on the tests.

The bottom line is that if you are using a point based system with an unweighted gradebook, then make the switch to a weighted gradebook using weights that are based off the points you have in the course. No one's grade is going to go down when you drop the lowest grade, most student's grade will go up, and if anyone questions you on it, explain how it was necessary to get Canvas to not lower people's grade. Most students stop complaining the instant their grade goes up.

I will throw out one additional warning. If you have extra credit, a weighted gradebook can really get screwy and throws a monkey wrench into all of this, but that's an entirely different conversation --- and one that's been had many times before in the Community.