You could have each one of your guests write something they are thankful for && put it up on the tree when they arrive for dinner. Then maybe before you eat the host/hostess could say each one. (Oh yeah, they would be anonymous of course)

Thankful Tree

Autumn Thanksgiving Tree! Saw this at Hobby Lobby and thought it was a great idea!

Thanksgiving day craft for the family (to remember who was present that day in years to come).