Additional assignment-related features and issues within Microsoft Teams for Education
Hi Denise,
I'm Nik, an independent advisor here to assist you with this.
Regarding grade criteria weighing, you need to make sure that you distribute weight total of percentage 100.
Tip: Enter a percentage of 100 if you’d like to weight some criteria more heavily than others. Make sure everything totals up to 100. If you need to, select Evenly distribute weights option to re-set all your percentages.
Also, you should be able to change the grading, please try removing existing rubric(click on "X" next to the assigned rubric and update assignment), click on "Add rubric" look for your previously created rubric and edit grading and weight as applicable.
I have tried to update grade and weight as per your requirement in my test and It worked just fine. please refer screenshot.
Please let me know if you have any question and I will be happy to assist.
Regards
Nik