Weekly quizzes (best 10 out of 12 quizzes counted)
In the Administration block, click on Grades
In the gradebook, click on Setup Tab, click on Gradebook setup
Put the weekly quizzes/assignment tasks into a category. To do this, click the Add category button at the bottom of the page
Give the category a name, for example 'Weekly quizzes'
If the assessment items are all marked out of different amounts (e.g. one quiz marked out of 10, another marked out of 15), set the Aggregation to Simple weighted mean of grades. This will ensure each assessment item is given equal weight
Click the check boxes next to each weekly assessment task, then use the Move selected items to menu to move to the category you just created
Your gradebook should now look like the following, with the weekly assessment items together in one folder (Weekly quizzes) and the standalone items separate
In the tab menu, switch to Full view
In the Keep the highest column, set the value for the 'Weekly quizzes' category to the number of items you wish to keep. For example, if you want to include the highest 10 scores, change this to 10.
From the topmost Aggregation menu, select Weighted mean of grades
In the Weight box next to each grade item or category, enter a number that represents how much this item is worth. For example, if an item is worth 5% of the topic total, enter 5. Remember to include a weight for the category (e.g. if you want the 'Weekly quizzes' items together to be worth 10%, enter 10 for the category).
At the bottom of the table, change the Topic total Max grade to 100