To create a transcript category, navigate to:
  1. onRecord > performance > grading
  2. Transcript Categories
  3. Edit
  4.  Add Transcript Category

To tie this to the team, navigate to:
  1. Core > school > sports & teams
  2. Find the team you want to tie it to and click the edit pencil button
  3. Click Grading and change the Transcript Category to the new Athletics one you created.