On the map you see stops and the lines between them. Each line says how many minutes the ride takes.
Two stops are printed thick - that is where you start and where you want to go. You are not looking for any route, but for the fastest one.
Here is the trick: the route with the fewest stops is never the fastest. Whoever simply takes the shortest line gets it wrong.
So do the math. Add up each route - for example 7 + 5 = 12 minutes - and compare the totals. The smallest one wins.
Example
For parents
What does this exercise practice?
The line network practices adding several numbers with a purpose - the child does not calculate because there is a sum on the page, but because otherwise it cannot decide. Because the fastest route is deliberately not the one with the fewest stops, the child really has to work out and compare every route. Along the way it meets two-digit numbers where they genuinely occur in daily life - in a timetable.
Common pitfalls
The most common mistake is taking the route with the fewest stops without doing any math - that one is never the fastest here. The second is dropping a number while adding up, because the finger slides along the line instead of tapping each number. And sometimes a route that looks much longer wins anyway.
How to practice at home
Take a real timetable or the network map from the bus. Pick two stops and work out together how long the ride takes on different lines. Or draw your own network with five places from your neighborhood and write walking minutes on the lines.
Related: The Picture Puzzle, The Sliding Robot