don't try too hard....they can always tell. Just be yourself, try not to be nervous. Something that worked like a charm for my bf's parents...I baked them some cookies before I went over. Even if you don't bake cookies since it's thanksgiving offer to bring a pie or something...or help out his mom in the kitchen. The way to my bf's family was through their stomaches! lol
anyway good luck! try to just relax && enjoy yourself
=]

First this is a great chance for you to either make a great connection or screw up your future for EVER.

----Do----
* Bring something such as bread or a nice side dish to go with dinner
* Use your manners and say thank you
* Be yourself
* Dress nicely and don't show to much skin
* Talk about your family and there traditions
* Enjoy yourself
* Help clean up
* Smile and try to be a crowd pleaser

-----Do NOT----
* Pig out on food
* Sit on your boyfriends lap
* be rude
* Forget your manners
* Insult his mothers cooking
* Say you hate anything
* Say your families traditions are better
* Yell, scream, shout, burp or fart around them
* forget who you are.

First, breathe.
Second, my mom used to say "don't walk in empty handed" - bringing a bottle of wine, a dessert or ....? ask your BF what they may need for the dinner....maybe you can bring your favorite dish!

That is a true ice-breaker and shows who you are and they can't help but "love" you like their son does (i have 2 so I know).

Last, don't try to hard, don't drink too much and listen a lot to engage his family in conversations about them - find out who they are - and again - they will find out who you are and again, they can't help but "love" you like their son!

Best of luck!

Ask your boyfriend if there is anything you should expect. I asked my boyfriend this and he forgot an important detail, his family prays before they eat! I did not start eating before this, but I was drinking water and we shouldn't touch our food before we pray at all. So ask if his family does anything like that.

Smile, listen much more than you talk, make an effort to try to talk to everyone, don't cling to your boyfriend (roam and chat freely- your independence will impress him!), keep it simple and positive when talking about yourself. Be aware of your choice of clothes. Good luck!

Just try and be the person that your boyfriend fell in love with. And be polite obviously.