Prerequisites: Create a blank course, with a clean gradebook. Set all sitewide gradebook settings to default, as if from a fresh install. Set Enabled aggregation methods to Natural and Weighted mean of grades. Enable webservices: Site Admin > Advanced Features > Enable web services, then enable the rest protocol Create a webservices service with the function core_grades_create_gradecategories, then create a token for this service: /admin/category.php?category=webservicesettings   Test default aggregation settings. Visit the gradebook setup page for the test course at /grade/edit/tree/index.php?id={COURSEID} Click ' Add category ' Verify checkbox ' Category total > Weight adjusted ' exists. Verify Text field ' Category total > Weight ' exists. Set the name to cat1 , and save the category. Verify gradebook category ' Cat1 ' has weight ' 0.0 '. Verify gradebook category ' Cat1 ' Weight override checkbox is ' Unticked '. Click edit on the cat1 category Verify checkbox ' W eight adjusted ' exists and is unticked. Verify checkbox ' Extra credit ' exists and is unticked. Verify text field ' Weight ' is   0.000 Verify Parent category is the course name Verify Parent aggregation is Natural Click checkbox 'Weight adjusted ' Verify 'Weight ' can be edited This verifies that the form is performing the same as prior for natural aggregation. Test weighted aggregation settings. Click  cancel on edit form. Click edit on course category. Set Aggregation to Weighted mean of grades Click Save Click Add Category Verify select Parent category is defaulted to course category. Verify Weight exists with value 1. Set Parent category to cat1 Verify checkbox Weight adjusted exists and is unchecked. Verify text field Weight is disabled Set select Parent category is to course category. Set Category name to 'cat2' Click Save Verify gradebook category 'cat2' has weight ' 1 '. Create another category, called 'cat3' under the main parent category, following steps in  Test weighted aggregation settings with a weight of 2.1 . Verify gradebook category ' c at3 ' has weight ' 1 '. Test weighted category creation via webservice call. Note the courseid for use in the webservice call. From a terminal, execute the following command, substituting in the courseid and webservice token, and verify the created course has a weighting of 1.2 after executing and reloading the gradebook: curl "{SITEURL}/webservice/rest/server.php?wstoken={TOKEN}&wsfunction=core_grades_create_gradecategories&moodlewsrestformat=json&courseid={COURSEID}&categories[ 0 ][fullname]=cat4&categories[ 0 ][options][aggregation]= 10 &categories[ 0 ][options][aggregationcoef]= 1.2