Initially, this problem could be introduced in a similar way as is suggested in the notes for Train Routes, but it would be good to focus more on looking for patterns and generalising in this case. You might like to work on the different routes for four stations as a whole class then ask small groups to look at
five and six stations so that you can pool results. Ask the children how they are recording the different routes - using initial capitals to stand for the stations is a great help, but share any good ways the pupils have found.
In order to look for a pattern in the numbers of routes, it might be helpful to make a table, something like this:
|Number of station visits||Number of different journeys|