When you you get your kids to write their letter to Santa? Have you done it yet? I usually feel it needs to be done around the start of December. If it's any earlier, they might change their mind about what they want for Christmas, if it's any later then Santa might not have time to get him (or her) self organized by Christmas!
Here's a free printable list for Santa which makes the job nice and easy:
Don't forget to colour the letters in - Santa will be delighted to get a letter which has been beautifully coloured in!
Enjoy! There is a printable pdf version here too.
Don't forget, according to Royal Mail the address to send your Father Christmas letters to is:
Santa/Father Christmas,
Santa's Grotto,
Reindeerland,
XM4 5HQ
Apparently if you send your Christmas list to this address (don't forget the stamp!) and include your name and address by 6th December you might even get a personalized reply back again...
Having said that we've always addressed our letters to Father Christmas to the North Pole and they seem to have all arrived safely...