I found a neat little Five in a Row type book. I thought you might would enjoy
it too, if you can find it in your library system.

The Story of a Brave St. Bernard Barry, by Bettina Hurlimann.

This is a story of how the St. Bernard dog got it's name. It comes from a Hospice in the Alps, located near the Great Saint Bernard Pass. The dogs date back to before Napoleon.

This would make a perfect week long study. You could locate the Swiss Alps.
Draw a picture of snow, and avalanches. Talk about who Napoleon was and why a war was taking place. You could check out picture books of the St. Bernard type
dogs. Then you could talk about what a hospice is. Another good discussion would be about Monks, what a Prior is, how they dressed a long time ago. You could talk about the laterns they used. One day you might want to draw a picture of a St. Bernard.