@WATax  Classes are great but the best refresher course is to read Pub 17 before the start of every tax season.  Not that I take my own advice on that anymore, but I probably should.  I'm not taking new clients and the old ones are generally dull and boring, that's why I hang out here looking for new questions.  Do they still publish a print version, or do you have to download the pdf and use your own paper and ink?  And I notice the publication date for the last edition was in March 2024.