To modify game points, first select the student or students you want. To select several students, go to the “Teams” or “Class” view and check them in the “Apply to” column:
Click on the white +/- button to adjust any stat values. Enter a positive number to add, or put a negative sign before the number to subtract.
You'll want to make sure you're using either Chrome, Safari, or Edge when doing this. (Sometimes unsupported browsers, such as Firefox or Internet Explorer, can create display issues with the negative sign.)