A christmas Assessment!!Pls!

1) Christmas dinner: turkey with stuffing, mashed potatoes with gravy and cranberry sauce, ham, eggnog, pudding, mince pies, brownies, chocolate mousse etc...

Different countries/cultures have dinner customs and traditions, I'd say go with England.

http://en.wikipedia.org/wiki/Christmas_dinner

2) Most people and the Bible would say it's the birth of Jesus Christ but scientists say it has more to do with astrology (天文/占星學)
Other cultures have different explanations on the origins of Christmas

http://en.wikipedia.org/wiki/Christmas#History

3) Roman Catholics and Anglicans: go to midnight Mass on the night of Christmas eve (the night between the 24th and 25th). Other similar religions have communions or solemn gatherings. Some have Nativity (耶穌誕生) performances as well.
Christmas eve is also the time Santa Claus visits children at their houses. He comes from the Arctic with his reindeers and goes down the chimneys of houses. Kids would leave cookies and milk by the Christmas tree for him.

Good luck!