You have made an excellent suggestion, and perhaps many families will adopt it as a practice this Thanksgiving. My only caution would be to be sure you don't embarrass anyone, since some may find this easier to do than others. Perhaps instead of having everyone read their whole list aloud, you might have them name their top two or three choices.
Even if we don't have each family member make an actual list, it's still important for us to pause and think about the blessings God has given us. After all, everything we have comes from His hands; even if we worked for it or earned it, He still gave us the ability and the opportunity to do it. The Bible reminds us that "everything in heaven and earth is yours. ... Wealth and honor come from you" (1 Chronicles 29:11-12). Thanksgiving is a time to remember this truth.
May you also remember this Thanksgiving not only the obvious gifts that God has given you, but His spiritual blessings, as well. The greatest gift of all is Jesus Christ, and the salvation God offers us in Him. Is Christ the center of your life and your family?
"Thanksgiving" literally means a time for "giving thanks." May this be true of each of you who are reading this today, as you pause to "Give thanks to the Lord, for he is good. His love endures forever" (Psalm 136:1).