book title and author?

[Elaine]

i was a primary education student in NZ for 6 months a few years ago and during one of the english lessons the lecturer talked about a children's christmas book.  it was aimed at children who no longer believed in santa and it was to do with a child who met an old man who I think told him about or gave him a key.  there might have been a train involved and at the end the boy found the key in his pocket.  I know this all sounds a bit absurd but if anyone recalls the book or its author can you let me know? 

[Patch49]

There is a section caled Booksleuth on http://www.abebooks.co.uk/ where people enter queries like this and get answers

[Dulcinea]

It actually sounds a bit like "The Polar Express".  He was not given a key, but a bell.  As he got older he could no longer hear the bell ring.  It represented a belief in magic and Santa Claus.  The Polar Express is a train that takes him to the North Pole on Christmas Eve.  It is a Caldecott (art) or Newberry (book) winner and this Christmas it is going to be an animated movie from Fox with Tom Hanks.  You would have to look up the author, but it is a classic so you should have no trouble.