How to Make a Leaderboard System in Google Spreadsheets

I am an Eighth Grader and I am trying to make a leaderboard program using Google Spreadsheets that calculates how many different states a certain class has gotten. I don't know how to make it so that it will COUNTUNIQUE the number of times that a certain class has another unique state that a donation has come from. I know how to make the part of the leaderboard that displays the results, but I need help in the part that calculates how many different states (ie: FL, GA, TN, AK) a certain teacher/classroom has at once, which I can then order from highest to lowest and use QUERY to drop it into my leaderboard. Hope that one of you can help!

Here is an example of the spreadsheet I want to order by teacher and state.

Solution

If these are the results you are looking for:

SO26394513 example

then a pivot table should suit, with Teacher added to Rows, State/Province/Region/County/Territory/Prefecture/Republic added to Values and Summarise by: COUNTUNIQUE.