Drop the Lowest Grade
From BbWiki
To drop the lowest grade, use a weighted column and categories.
Create a category by going to the Grade Center and selecting "Manage" and then "Categories". Create a category that fits the type of assignments that you will want to drop the lowest grade. For example, if you want to drop the lowest homework grade, make a "Homework" category.
Create a new weighted column by selecting "Add Calculated Column" and then "Weighted Column". Fill out section 1 with the appropriate information and then in Section 3, select the category of interested and click on the arrow next to the category listings to set the options. You will have to ability to set weighting options and a variety of choices for dropping the highest or lowest grades.
Note: The "total" calculated column also gives the option to drop the lowest grade, but as of May 2009, there is a known bug that prevents the total column type from dropping grades.
