cancel
Showing results for 
Search instead for 
Did you mean: 
bfran3
Community Member

How do I make one assignment out of a group optional using a weighted grading system?

Jump to solution

I am using a new weighted graded system this quarter, and I am struggling with two interconnected issues. First, students in my course are required to complete a total of 5 group response papers out of 6 possible. In this scenario, they have the option of skipping one of the six, or they can complete all of them and the 6th one will count as extra credit. I'm struggling with how to set this up in the Assignment Groups. I thought about making the 6th one an extra credit assignment, but how do I account for students completing the 6th assignment as one of the required 5 (and skipping one in the middle, say the 3rd paper)? 

I also thought about putting all six papers in the same assignment group (with no extra credit group), and then adding a drop one zero score rule, but some students won't have any zeros (because they will have completed all six papers so they could earn extra points)

Any insights would be much appreciated!

1 Solution

Accepted Solutions
James
Navigator

 @bfran3 ,

The good news is that there is a relatively simple way to accomplish this for assignments where you manually assign a grade (not quizzes).

 

Let me give you a few approaches. All three require that you put in zeros for missing assignments. I list them in the order I thought of them, but the second one is simpler and involves less work on your part. The third one is just messed-up, but it works mathematically. It was an afterthought when I wrote there's no way to ... but then realized there was a way, it's just evil and a lot more work on your part and gives a false sense of security to the students.

Two assignment groups -- flexibility

I would set up two assignment groups, one for the assignments and one for the extra credit. 

In the primary assignment group, you would put all six assignments and add an assignment rule to drop the lowest grade.

In the secondary (extra credit) group, you would manually transfer the grade from the dropped assignment in the primary group. There's no way within the web interface or rules that you can setup to automatically transfer the lowest grade to a new group. For small classes, it's quickest to manually transfer them by retyping them. For larger classes, you may want to export the gradebook, perform the calculations there, and then import the new column back into Canvas.

This approach has the benefit of you allowing the extra credit one to be a different weight than the other 5. For example, if your primary group was 30% of the grade, then each of the 5 items would be 6%. But let's say you didn't want the extra credit to be 6% of the grade, you only wanted it to be 3% of the grade. You could set up the secondary group to be worth 3% of the grade.

Make sure you go through and put in 0's for any assignments in the primary group that are not completed or it will throw things off by dropping one of the submitted ones so they actually get 4 grades rather than 5.

This approach would also work for quizzes where you cannot set a point total to be 0.

One assignment group -- simplicity

Create one assignment group that has all six assignments in it and make one of the assignments, say the last one, worth 0 points.

Canvas takes the sum of the student scores and divides it by the sum of the possible points (for assignments with a grade). If the student completes a sixth assignment, they don't the amount possible doesn't increase.

The question is what about the person who skips assignment 3 and does assignment 6. In this case, the grade will be off UNTIL you put in a 0 for assignment 3. Once you put in a 0 for assignment 3, then it works itself out.

Here's a little spreadsheet to show the calculations. I assumed each assignment was worth 10 points. The scored row is what the student scored for that assignment and the possible row is what Canvas added towards the possible score.

Assignment#1#2#3#4#5#6TotalPercent
A78%
scored10978539
possible101010101050
B105%
scored109851042
possible10101010040
C84%
scored1090851042
possible1010101010050
D98%
scored1097851049
possible1010101010050
E100%
scored101010101050
possible101010101050
F120%
scored10101010101060
possible1010101010050

Student A shows that it is okay to leave the last one completely empty and not put a 0 for it. However, it is imperative that any non-zero assignment that a student did not complete get a 0.


Student B and C are the same except that for student C you've put a 0 down for the missing assignment 3. Without the 0 in there (student B), Canvas doesn't count the 10 points for the assignment and so the student only has 40 possible points and got extra credit even though they only did five assignments. With the 0 in there (student C), Canvas counts the 10 points for assignment 3 and so the student has 50 possible points, but since they got a 0 for one of them it's not extra credit.

Student D is the same as B and C except they did assignment 3 (or the same as A but they did assignment 6).

Students E and F are there to show what happens when you have perfect scores. Student E scored perfect scores on the first 5 and got 100%. Student F scored perfect scores on all six and got 120%

If you want the extra credit to be weighted differently than the rest, then you shouldn't use the second approach.

To stress the importance of putting in 0's before determining the final grade, here's student G who only completed the first assignment but the teacher didn't put in 0's for the rest. Student H is the same, but with 0's in for all of the other assignments (except perhaps the 0 point assignment 6 -- it really doesn't matter). As you can see, we don't want the student who only did one assignment to get 100%.

Assignment#1#2#3#4#5#6TotalPercent
G100%
scored1010
possible1010
H020%
scored10000010
possible101010101050

Finally, I did these calculations with Excel, but to show you that it's really the way Canvas works, I created an assignment group (named Becky) in my sandbox course and entered some of the grades, making sure to put in 0's for all of the grades. I've only got 3 students to play with in my sandbox, but here are students C, D, and F from above.

263824_pastedImage_38.png

Here are students A, B, and E

263828_pastedImage_39.png

Finally, here are students G and H and H (with a 0 for assignment 6)

263829_pastedImage_40.png

One Assignment Group - Twisted, Convoluted, Evil, Don't do this!!!

Make one assignment group with all six assignments in it and make each assignment worth points (don't make any worth 0 points).

However, when you enter the grades into the gradebook, you need to enter an extra 20% over what they score. Keeping with the same example as before, if the assignment was worth 10 points and they scored 9, then you would add an extra 20% of 9 = 1.8 points onto the 9 to give them 10.8 points for the assignment. You can also accomplish this by multiplying the original score by 120% (1.20 as a decimal).

With this approach, it is absolutely imperative that you put in 0's for all missing assignments.

In this spreadsheet, all six assignments are worth 10 points. The scored row is what they originally scored and the bonus row is 120% of that. The bonus row is what you would put the grade into Canvas for their grade.

Assignment#1#2#3#4#5#6TotalPercent
A94%
scored10978539
bonus1210.88.49.6646.8
possible101010101050
B78%
scored109785039
bonus1210.88.49.66046.8
possible10101010101060
C84%
scored1090851042
bonus1210.809.661250.4
possible10101010101060
D98%
scored1097851049
bonus1210.88.49.661258.8
possible10101010101060
E120%
scored101010101050
bonus121212121260
possible101010101050
F120%
scored10101010101060
bonus12121212121272
possible10101010101060
G120%
scored1010
bonus1212
possible1010
H020%
scored100000010
bonus120000012
possible10101010101060

Student A is messed up because you didn't put in a 0 for the last assignment. They scored 39 points out of 50 (78%), but because you added the 20% bonus without putting in a 0, it took it as 46.8 points out of 50 (94%) rather than 46.8 points out of 60 (78%).


Student B is the same as A but with a 0 entered for that sixth assignment that they didn't do. Now it's 46.8 points out of 60 (78%) and the same they would have had without the 20%.

Student C didn't do assignment 3, but got 42 points out of 50 (84%). With the bonus, they got 50.4 out of 60 (84%).


Student D did all six assignments and would have had 49 out of 50 (98%). With the bonus, they got 58.8 out of 60 (98%).


Student E got perfects on five assignments and should have had 50 out of 50 (100%), but because you didn't put in 0 for the six assignment, the bonus gives them 60 out of 50 (120%). If you would have put in the 0 for assignment 6, then it would have been 60 out of 60 (100%).

Student F is the same as E, but with 10's for all six assignments so they got 60 out of 50 (120%). With the bonus, they got 72 out of 60 (120%).

Student G illustrates the reason you must put in 0's for missing assignments. They got 10 out of 10 (100%) since Canvas only counts assignments with a grade for the possible score. They should have been 10 out of 50 (20%), but because of the bonus they got 12, it's 12 out of 10 (120%).

Student H is the same as G, but with the extra 0's put in there. Now they have 10 out of 50 (20%) but with the bonus, they got 12 out of 60 (20%).

This technique is dangerous, but it has potential if you're into mind games. Throughout the semester, their grade would be over-inflated, but it would give them a taste of what would happen if they do the last assignment and get the bonus. They see a big drop in their percentages if they don't.

By the way, the 20% is because you were counting 5 assignments and 100%/5 = 20%. If you had 8 assignments and wanted to drop 1, then you would need to use a bonus of 100%/7 = really freakingly ugly math.

What won't work

What won't work is putting all six assignments into the same assignment group, making them all worth the full points, and not dropping any grades. Then all six grades will be counted as part of the group and there will be no way to assign extra credit unless you add extra points to each assignment as shown in the third technique.

View solution in original post

4 Replies
James
Navigator

 @bfran3 ,

The good news is that there is a relatively simple way to accomplish this for assignments where you manually assign a grade (not quizzes).

 

Let me give you a few approaches. All three require that you put in zeros for missing assignments. I list them in the order I thought of them, but the second one is simpler and involves less work on your part. The third one is just messed-up, but it works mathematically. It was an afterthought when I wrote there's no way to ... but then realized there was a way, it's just evil and a lot more work on your part and gives a false sense of security to the students.

Two assignment groups -- flexibility

I would set up two assignment groups, one for the assignments and one for the extra credit. 

In the primary assignment group, you would put all six assignments and add an assignment rule to drop the lowest grade.

In the secondary (extra credit) group, you would manually transfer the grade from the dropped assignment in the primary group. There's no way within the web interface or rules that you can setup to automatically transfer the lowest grade to a new group. For small classes, it's quickest to manually transfer them by retyping them. For larger classes, you may want to export the gradebook, perform the calculations there, and then import the new column back into Canvas.

This approach has the benefit of you allowing the extra credit one to be a different weight than the other 5. For example, if your primary group was 30% of the grade, then each of the 5 items would be 6%. But let's say you didn't want the extra credit to be 6% of the grade, you only wanted it to be 3% of the grade. You could set up the secondary group to be worth 3% of the grade.

Make sure you go through and put in 0's for any assignments in the primary group that are not completed or it will throw things off by dropping one of the submitted ones so they actually get 4 grades rather than 5.

This approach would also work for quizzes where you cannot set a point total to be 0.

One assignment group -- simplicity

Create one assignment group that has all six assignments in it and make one of the assignments, say the last one, worth 0 points.

Canvas takes the sum of the student scores and divides it by the sum of the possible points (for assignments with a grade). If the student completes a sixth assignment, they don't the amount possible doesn't increase.

The question is what about the person who skips assignment 3 and does assignment 6. In this case, the grade will be off UNTIL you put in a 0 for assignment 3. Once you put in a 0 for assignment 3, then it works itself out.

Here's a little spreadsheet to show the calculations. I assumed each assignment was worth 10 points. The scored row is what the student scored for that assignment and the possible row is what Canvas added towards the possible score.

Assignment#1#2#3#4#5#6TotalPercent
A78%
scored10978539
possible101010101050
B105%
scored109851042
possible10101010040
C84%
scored1090851042
possible1010101010050
D98%
scored1097851049
possible1010101010050
E100%
scored101010101050
possible101010101050
F120%
scored10101010101060
possible1010101010050

Student A shows that it is okay to leave the last one completely empty and not put a 0 for it. However, it is imperative that any non-zero assignment that a student did not complete get a 0.


Student B and C are the same except that for student C you've put a 0 down for the missing assignment 3. Without the 0 in there (student B), Canvas doesn't count the 10 points for the assignment and so the student only has 40 possible points and got extra credit even though they only did five assignments. With the 0 in there (student C), Canvas counts the 10 points for assignment 3 and so the student has 50 possible points, but since they got a 0 for one of them it's not extra credit.

Student D is the same as B and C except they did assignment 3 (or the same as A but they did assignment 6).

Students E and F are there to show what happens when you have perfect scores. Student E scored perfect scores on the first 5 and got 100%. Student F scored perfect scores on all six and got 120%

If you want the extra credit to be weighted differently than the rest, then you shouldn't use the second approach.

To stress the importance of putting in 0's before determining the final grade, here's student G who only completed the first assignment but the teacher didn't put in 0's for the rest. Student H is the same, but with 0's in for all of the other assignments (except perhaps the 0 point assignment 6 -- it really doesn't matter). As you can see, we don't want the student who only did one assignment to get 100%.

Assignment#1#2#3#4#5#6TotalPercent
G100%
scored1010
possible1010
H020%
scored10000010
possible101010101050

Finally, I did these calculations with Excel, but to show you that it's really the way Canvas works, I created an assignment group (named Becky) in my sandbox course and entered some of the grades, making sure to put in 0's for all of the grades. I've only got 3 students to play with in my sandbox, but here are students C, D, and F from above.

263824_pastedImage_38.png

Here are students A, B, and E

263828_pastedImage_39.png

Finally, here are students G and H and H (with a 0 for assignment 6)

263829_pastedImage_40.png

One Assignment Group - Twisted, Convoluted, Evil, Don't do this!!!

Make one assignment group with all six assignments in it and make each assignment worth points (don't make any worth 0 points).

However, when you enter the grades into the gradebook, you need to enter an extra 20% over what they score. Keeping with the same example as before, if the assignment was worth 10 points and they scored 9, then you would add an extra 20% of 9 = 1.8 points onto the 9 to give them 10.8 points for the assignment. You can also accomplish this by multiplying the original score by 120% (1.20 as a decimal).

With this approach, it is absolutely imperative that you put in 0's for all missing assignments.

In this spreadsheet, all six assignments are worth 10 points. The scored row is what they originally scored and the bonus row is 120% of that. The bonus row is what you would put the grade into Canvas for their grade.

Assignment#1#2#3#4#5#6TotalPercent
A94%
scored10978539
bonus1210.88.49.6646.8
possible101010101050
B78%
scored109785039
bonus1210.88.49.66046.8
possible10101010101060
C84%
scored1090851042
bonus1210.809.661250.4
possible10101010101060
D98%
scored1097851049
bonus1210.88.49.661258.8
possible10101010101060
E120%
scored101010101050
bonus121212121260
possible101010101050
F120%
scored10101010101060
bonus12121212121272
possible10101010101060
G120%
scored1010
bonus1212
possible1010
H020%
scored100000010
bonus120000012
possible10101010101060

Student A is messed up because you didn't put in a 0 for the last assignment. They scored 39 points out of 50 (78%), but because you added the 20% bonus without putting in a 0, it took it as 46.8 points out of 50 (94%) rather than 46.8 points out of 60 (78%).


Student B is the same as A but with a 0 entered for that sixth assignment that they didn't do. Now it's 46.8 points out of 60 (78%) and the same they would have had without the 20%.

Student C didn't do assignment 3, but got 42 points out of 50 (84%). With the bonus, they got 50.4 out of 60 (84%).


Student D did all six assignments and would have had 49 out of 50 (98%). With the bonus, they got 58.8 out of 60 (98%).


Student E got perfects on five assignments and should have had 50 out of 50 (100%), but because you didn't put in 0 for the six assignment, the bonus gives them 60 out of 50 (120%). If you would have put in the 0 for assignment 6, then it would have been 60 out of 60 (100%).

Student F is the same as E, but with 10's for all six assignments so they got 60 out of 50 (120%). With the bonus, they got 72 out of 60 (120%).

Student G illustrates the reason you must put in 0's for missing assignments. They got 10 out of 10 (100%) since Canvas only counts assignments with a grade for the possible score. They should have been 10 out of 50 (20%), but because of the bonus they got 12, it's 12 out of 10 (120%).

Student H is the same as G, but with the extra 0's put in there. Now they have 10 out of 50 (20%) but with the bonus, they got 12 out of 60 (20%).

This technique is dangerous, but it has potential if you're into mind games. Throughout the semester, their grade would be over-inflated, but it would give them a taste of what would happen if they do the last assignment and get the bonus. They see a big drop in their percentages if they don't.

By the way, the 20% is because you were counting 5 assignments and 100%/5 = 20%. If you had 8 assignments and wanted to drop 1, then you would need to use a bonus of 100%/7 = really freakingly ugly math.

What won't work

What won't work is putting all six assignments into the same assignment group, making them all worth the full points, and not dropping any grades. Then all six grades will be counted as part of the group and there will be no way to assign extra credit unless you add extra points to each assignment as shown in the third technique.

View solution in original post

I thought of another evil, twisted, don't use, but easier on the instructor -- method after getting some sleep.

This is like the 3rd approach and still has the pitfalls of their grades are over-inflated throughout the semester, it's difficult for the students to understand, and you absolutely have to put a 0 in for every assignment they don't do

Instead of giving a manually calculated bonus to each student, you could just discount the points of the assignment.

If assignments are worth 10 points each then divide 10 by 1.2 to get 8.33333333. Make each assignment worth 8.3333333 points and then just put in the normal score for the student.

There's a slight problem that if you go to two decimals, then six 8.33's only add up to 49.8 instead of 50, so a student who had 39 points would get 39/49.8 = 78.31% instead of 78%. You could fix that with 8.34 for two of them. It doesn't really matter which two as long as you enter 0's for all the missing grades when you're done so that they're counted.

Still, I do not recommend this method for all the same evil, twisted, hackish ways the third one in the original message was bad, but at least the math is easier.

Note that if you did have 8 assignments and wanted to keep 7, then you would need to multiply each score multiply by 8/7, resulting in the really freakingly ugly math, but if you wanted to scale then assignment possible points, then you would divide by 8/7, which is equivalent to multiplying by 7/8. That makes each 10 point assignment worth 8.75 points, which doesn't cause rounding issues like dividing by 6/5 and getting 8.3333333 when there are 6 assignments.

bfran3
Community Member

Wow  @James ! This is incredible! I cannot tell you how long I beat my head against the wall yesterday trying to figure out a way to make this work without being too evil to students, or too complicated for myself and my TA! Option Two-The One Assignment Group Simplicity option in your first reply is exactly what I was looking for! Thank you so much for your thoughtful insights, and the math lessons along the way!!! 

I figured the second one was the one you wanted, but I have a tendency to put things down in the order I think of them and don't go back and move them around to make more sense later. I'm glad you were able to pull out the important stuff from the volumes of fluff.