3 green things you're thankful for
1. Trees
2. Money
3. Green salad
3 things you're grateful for beginning with the letter T
(I love some of the others mentioned, and almost changed some of my answers, but I'll go with my original answers.)
1. Teddy bears (I got one from my secret Santa at work this week.

)
2. Time
3. Teachers
3 sweet treats
1. Dove Dark Chocolate
2. Lindt Dark Chocolate truffles
3. Chocolate ice cream.
What? Me? a chocoholic? Where would you EVER get that idea?!?
3 holiday things you're grateful for
1. Christmas carols, including a lot of the contemporary ones. I love music, but I think you've probably guessed that by now from some of my other answers.
2. Christmas Eve and, since it's on a Sunday this year, Christmas morning services at church!
3. This is included in 1, but becuase I love promoting it, the Behold the Lamb of God album by Andrew Peterson. it's just an amazing collection of songs that tells the Christmas story from Genesis to Revelation, and has some of the most powerful lyrics I've ever heard.