You could exchange 2 items (carvings or whatever) for a small present, 3 for a medium, 4 for a large and 5 for an extra large present.
These presents would have to be salvaged (to represent opening the present) and will contain a special Christmas item, similar to the halloween items.
If you exchanged for a larger present, you would have a chance of getting some extra treats too. Perhaps a little gold, a party hat, a whistle, or...think about this one...a joke.
