How do I enter the certificate # in the Education Expense Credit section (specifically for the Georgia GOAL Scholarship Program) on my Georgia state return?

You enter that information in the Georgia Credits section.  Scroll down to "Individual and Business Credits" it's at the bottom of the page.  Click on Start (or Revisit).  In the drop down menu, select #125 - Qualified Education Expense Credit. (See screen shot below) Enter your Certificate information and click on Continue.